+publisher:"University of Arizona" +contributor:("Zeng, Xubin")

University of Arizona

1. Lytle, William. Coupled Evaluation of Below- and Above-Ground Energy and Water Cycle Variables from Reanalysis Products Over Five Flux Tower Sites in the U.S.

Degree: 2015, University of Arizona

URL: http://hdl.handle.net/10150/595636

► Reanalysis products are widely used to study the land-atmosphere exchanges of energy, water, and carbon fluxes, and have been evaluated using in situ data above… (more)

Subjects/Keywords: Reanalysis; Snow cover; Atmospheric Sciences; Land-atmosphere interactions

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APA (6^th Edition):

Lytle, W. (2015). Coupled Evaluation of Below- and Above-Ground Energy and Water Cycle Variables from Reanalysis Products Over Five Flux Tower Sites in the U.S. (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/595636

Chicago Manual of Style (16^th Edition):

Lytle, William. “Coupled Evaluation of Below- and Above-Ground Energy and Water Cycle Variables from Reanalysis Products Over Five Flux Tower Sites in the U.S. ” 2015. Masters Thesis, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/595636.

MLA Handbook (7^th Edition):

Lytle, William. “Coupled Evaluation of Below- and Above-Ground Energy and Water Cycle Variables from Reanalysis Products Over Five Flux Tower Sites in the U.S. ” 2015. Web. 05 Mar 2021.

Vancouver:

Lytle W. Coupled Evaluation of Below- and Above-Ground Energy and Water Cycle Variables from Reanalysis Products Over Five Flux Tower Sites in the U.S. [Internet] [Masters thesis]. University of Arizona; 2015. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/595636.

Council of Science Editors:

Lytle W. Coupled Evaluation of Below- and Above-Ground Energy and Water Cycle Variables from Reanalysis Products Over Five Flux Tower Sites in the U.S. [Masters Thesis]. University of Arizona; 2015. Available from: http://hdl.handle.net/10150/595636

University of Arizona

2. Reeves Eyre, James Edward Jack. Evaluation of Greenland Near Surface Air Temperature Datasets .

Degree: 2016, University of Arizona

URL: http://hdl.handle.net/10150/622907

► Near-surface air temperature (SAT) over Greenland has important effects on mass balance of the ice sheet, but it is unclear which SAT datasets are reliable… (more)

Subjects/Keywords: Climatology; Cryosphere; Glaciology; Greenland; Ice sheet; Air temperature

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APA (6^th Edition):

Reeves Eyre, J. E. J. (2016). Evaluation of Greenland Near Surface Air Temperature Datasets . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/622907

Chicago Manual of Style (16^th Edition):

Reeves Eyre, James Edward Jack. “Evaluation of Greenland Near Surface Air Temperature Datasets .” 2016. Masters Thesis, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/622907.

MLA Handbook (7^th Edition):

Reeves Eyre, James Edward Jack. “Evaluation of Greenland Near Surface Air Temperature Datasets .” 2016. Web. 05 Mar 2021.

Vancouver:

Reeves Eyre JEJ. Evaluation of Greenland Near Surface Air Temperature Datasets . [Internet] [Masters thesis]. University of Arizona; 2016. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/622907.

Council of Science Editors:

Reeves Eyre JEJ. Evaluation of Greenland Near Surface Air Temperature Datasets . [Masters Thesis]. University of Arizona; 2016. Available from: http://hdl.handle.net/10150/622907

University of Arizona

3. Dawson, Nicholas. Assessment and Improvement of Snow Datasets Over the United States .

Degree: 2017, University of Arizona

URL: http://hdl.handle.net/10150/624535

► Improved knowledge of the cryosphere state is paramount for continued model development and for accurate estimates of fresh water supply. This work focuses on evaluation… (more)

▼ Improved knowledge of the cryosphere state is paramount for continued model development and for accurate estimates of fresh water supply. This work focuses on evaluation and potential improvements of current snow datasets over the United States. Snow in mountainous terrain is most difficult to quantify due to the slope, aspect, and remote nature of the environment. Due to the difficulty of measuring snow quantities in the mountains, the initial study creates a new method to upscale point measurements to area averages for comparison to initial snow quantities in numerical weather prediction models. The new method is robust and cross validation of the method results in a relatively low mean absolute error of 18% for snow depth (SD). Operational models at the National Centers for Environmental Prediction which use Air Force Weather Agency (AFWA) snow depth data for initialization were found to underestimate snow depth by 77% on average. Larger error is observed in areas that are more mountainous. Additionally, SD data from the Canadian Meteorological Center, which is used for some model evaluations, performed similarly to models initialized with AFWA data. The use of constant snow density for snow water equivalent (SWE) initialization for models which utilize AFWA data exacerbates poor SD performance with dismal SWE estimates. A remedy for the constant snow density utilized in NCEP snow initializations is presented in the next study which creates a new snow density parameterization (SNODEN). SNODEN is evaluated against observations and performance is compared with offline land surface models from the National Land Data Assimilation System (NLDAS) as well as the Snow Data Assimilation System (SNODAS). SNODEN has less error overall and reproduces the temporal evolution of snow density better than all evaluated products. SNODEN is also able to estimate snow density for up to 10 snow layers which may be useful for land surface models as well as conversion of remotely-sensed SD to SWE. Due to the poor performance of previously evaluated snow products, the last study evaluates openly-available remotely-sensed snow datasets to better understand the strengths and weaknesses of current global SWE datasets. A new SWE dataset developed at the University of Arizona is used for evaluation. While the UA SWE data has already been stringently evaluated, confidence is further increased by favorable comparison of UA snow cover, created from UA SWE, with multiple snow cover extent products. Poor performance of remotely-sensed SWE is still evident even in products which combine ground observations with remotely-sensed data. Grid boxes that are predominantly tree covered have a mean absolute difference up to 87% of mean SWE and SWE less than 5 cm is routinely overestimated by 100% or more. Additionally, snow covered area derived from global SWE datasets have mean absolute errors of 20%-154% of mean snow covered area. Advisors/Committee Members: Zeng, Xubin (advisor), Zeng, Xubin (committeemember), Avellano, Avelino (committeemember), Crimmins, Michael (committeemember), Brown, Paul (committeemember).

Subjects/Keywords: initialization; model; parameterization; remote sensing; Snow; snow water equivalent

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APA (6^th Edition):

Dawson, N. (2017). Assessment and Improvement of Snow Datasets Over the United States . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/624535

Chicago Manual of Style (16^th Edition):

Dawson, Nicholas. “Assessment and Improvement of Snow Datasets Over the United States .” 2017. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/624535.

MLA Handbook (7^th Edition):

Dawson, Nicholas. “Assessment and Improvement of Snow Datasets Over the United States .” 2017. Web. 05 Mar 2021.

Vancouver:

Dawson N. Assessment and Improvement of Snow Datasets Over the United States . [Internet] [Doctoral dissertation]. University of Arizona; 2017. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/624535.

Council of Science Editors:

Dawson N. Assessment and Improvement of Snow Datasets Over the United States . [Doctoral Dissertation]. University of Arizona; 2017. Available from: http://hdl.handle.net/10150/624535

University of Arizona

4. Holland, Madeleine. Snowpack over the Contiguous United States: Drivers, Trends, and Vegetation Cover Effects .

Degree: 2020, University of Arizona

URL: http://hdl.handle.net/10150/642020

► Cycles of snow accumulation and melt are primarily driven by precipitation and temperature, and the impact of these drivers can be influenced by factors including… (more)

Subjects/Keywords: forest; Snow; SWE

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APA (6^th Edition):

Holland, M. (2020). Snowpack over the Contiguous United States: Drivers, Trends, and Vegetation Cover Effects . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/642020

Chicago Manual of Style (16^th Edition):

Holland, Madeleine. “Snowpack over the Contiguous United States: Drivers, Trends, and Vegetation Cover Effects .” 2020. Masters Thesis, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/642020.

MLA Handbook (7^th Edition):

Holland, Madeleine. “Snowpack over the Contiguous United States: Drivers, Trends, and Vegetation Cover Effects .” 2020. Web. 05 Mar 2021.

Vancouver:

Holland M. Snowpack over the Contiguous United States: Drivers, Trends, and Vegetation Cover Effects . [Internet] [Masters thesis]. University of Arizona; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/642020.

Council of Science Editors:

Holland M. Snowpack over the Contiguous United States: Drivers, Trends, and Vegetation Cover Effects . [Masters Thesis]. University of Arizona; 2020. Available from: http://hdl.handle.net/10150/642020

University of Arizona

5. Brunke, Michael. Assessing and Improving the Representation of Hydrologic Processes in Atmospheric, Ocean, and Land Modeling and Dataset Generation .

Degree: 2015, University of Arizona

URL: http://hdl.handle.net/10150/560855

► Water is essential to life on Earth. Since water exists in all three phases (solid, liquid, and gas) on Earth, it exists in various reservoirs… (more)

▼ Water is essential to life on Earth. Since water exists in all three phases (solid, liquid, and gas) on Earth, it exists in various reservoirs throughout the planet that compose the hydrologic cycle, and its movement through these reservoirs requires energy. Thus, water is a key component of the energy balance of the Earth. Despite its importance, its representation in modeling and dataset generation is problematic. Here, the depiction of three phenomena, ocean surface turbulent fluxes, humidity inversions, and groundwater, are assessed, and suggestions for improvements of their representations are made. First, ocean surface turbulent fluxes, including those of moisture (latent heat flux), heat (sensible heat flux), and momentum (wind stress), from reanalysis, satellite-derived, and combined products which are commonly used to produce climatologies and to evaluate global climate models are compared to in situ observations from ship cruises to ascertain which products are the least problematic. The National Aeronautics and Space Administration’s reanalysis, the Modern Era Retrospective Analysis for Research and Applications, is the least problematic for all three fluxes, while a couple of others are the least problematic for only one of the three fluxes. Also, the product biases are disaggregated into uncertainties from the grid cell mean quantities, or bulk variables, used plus the residual uncertainties which includes the algorithm uncertainties due to the parameterization used to relate the small-scale turbulent processes to the large-scale bulk variables. The latter contribute the most to the majority of product latent heat fluxes, while both uncertainties can contribute the most to product sensible heat fluxes and wind stress. Thus, both algorithms and bulk variables need to be improved in ocean surface flux datasets. Second, humidity inversion climatologies in five reanalyses are evaluated. Humidity inversions, similar to its thermal counterpart, are layers in which specific humidity increases with height rather than the usual decrease with height. These are especially persistent in the polar regions in autumn and winter. However, Arctic inversions are the strongest in summer corresponding to the time of year that low cloud cover is the highest. Comparing the reanalysis inversions to radiosonde observations reveals some problems with the realization of humidity inversions in reanalyses including the misrepresentation of the diurnal cycle and of the overproduction of inversions in areas outside the polar regions. Finally, the simulation of groundwater in the Community Land Model (CLM) as used in the Community Earth System Model is made more realistic by including variable soil thickness. Because the bottom of the model soil column is placed at effectively bedrock, the unconfined aquifer model currently used in CLM is removed and a zero bottom water flux is put in place. The removal of the unconfined aquifer allows the simulation of groundwater to not be treated separately from soil moisture. The model is most… Advisors/Committee Members: Zeng, Xubin (advisor), Dominguez, Francina (committeemember), HIrschboeck, Katherine (committeemember), Russell, Joellen L. (committeemember), Serra, Yolande (committeemember), Zeng, Xubin (committeemember).

Subjects/Keywords: Humidity inversions; Land surface modeling; Ocean surface fluxes; Variable soil thickness; Atmospheric Sciences; Climate

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APA (6^th Edition):

Brunke, M. (2015). Assessing and Improving the Representation of Hydrologic Processes in Atmospheric, Ocean, and Land Modeling and Dataset Generation . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/560855

Chicago Manual of Style (16^th Edition):

Brunke, Michael. “Assessing and Improving the Representation of Hydrologic Processes in Atmospheric, Ocean, and Land Modeling and Dataset Generation .” 2015. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/560855.

MLA Handbook (7^th Edition):

Brunke, Michael. “Assessing and Improving the Representation of Hydrologic Processes in Atmospheric, Ocean, and Land Modeling and Dataset Generation .” 2015. Web. 05 Mar 2021.

Vancouver:

Brunke M. Assessing and Improving the Representation of Hydrologic Processes in Atmospheric, Ocean, and Land Modeling and Dataset Generation . [Internet] [Doctoral dissertation]. University of Arizona; 2015. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/560855.

Council of Science Editors:

Brunke M. Assessing and Improving the Representation of Hydrologic Processes in Atmospheric, Ocean, and Land Modeling and Dataset Generation . [Doctoral Dissertation]. University of Arizona; 2015. Available from: http://hdl.handle.net/10150/560855

6. Bashir, Furrukh. Hydrometeorological Variability over Pakistan .

Degree: 2017, University of Arizona

URL: http://hdl.handle.net/10150/626357

► Pakistan, as an agriculture based economy, is vulnerable to various hydrometeorological hazards ranging from tropical cyclones, thunderstorms, tornadoes, drought, rain, hail, snow, lightning, fog, wind,… (more)

▼ Pakistan, as an agriculture based economy, is vulnerable to various hydrometeorological hazards ranging from tropical cyclones, thunderstorms, tornadoes, drought, rain, hail, snow, lightning, fog, wind, temperature extremes, air pollution, and climatic change. However, three of the most pressing challenges in terms of water resource availability, that are different in nature, but are inter-linked to each other are discussed over here. We begin with the Karakoram Anomaly that is considered as one of the most mysterious and most speculated phenomena on Planet Earth. Though, it is confined to the glaciers in the eastern Hindukush, western Karakoram and northwestern Himalayan mountain ranges of Northern Pakistan that are not responding to global warming in the same manner as their counterparts elsewhere, because, their retreat rates are less than the global average, and some are either stable or growing. However, the Karakoram Anomaly has baffled scientific society for more than a decade since its earliest discovery in the year 2005. The reasons of the Karakoram anomaly were mainly associated to physiography of the area and role of climate was considered marginal till now, as climate is influencing glaciers differently all over the globe. Here, for the first time, we present a hydro-meteorological perspective based on five decades of synoptic weather observations collected by the meteorological network of Pakistan. Analysis of this unique data set indicates that increased regional scale humidity, cloud cover, and precipitation, along with decreased net radiation, near-surface wind speed, potential evapotranspiration and river flow, especially during the summer season, represent a substantial change in the energy, mass and momentum fluxes that are facilitating the establishment of the Karakoram Anomaly. In turn, it is influencing the availability of glacier melt in River Indus in summer season. Secondly, we developed a hydrometeorological data sets for Pakistan as they are extremely important for water related impact studies and future climate change scenarios. Presently, major sources of gridded temperature and precipitation data generation are in-situ observations, satellite retrieved information and outputs from numerical models. However, each has its own merits and demerits. Among them gridded observed data sets are considered superior if the gauge density is better. Unfortunately, precipitation gauge network of Pakistan is poorly presented in prior gridded products. Therefore, a daily in-situ observation based, 0.05º×0.05º gridded temperature and precipitation data set for Pakistan, for the period of 1960-2013 is developed. It is named as PAK-HYM-1.0, that is an abbreviation of Pakistan and Hydrometeorology, and 1.0 indicates that it is the first version. This data set is developed by utilizing data from 67 meteorological stations of Pakistan. This number of observation sites is 2 to 4 times higher than that used in prior similar products, and this product can be adopted as an operational information product that can… Advisors/Committee Members: Gupta, Hoshin V (advisor), Zeng, Xubin (advisor), Gupta, Hoshin V. (committeemember), Zeng, Xubin (committeemember), Galarneau, Thomas J. (committeemember), Hazenberg, Pieter (committeemember).

Subjects/Keywords: Climatic Disasters; Glaciers; Hydrometeorology; Pakistan; Precipitation; Temperature

10 more images…

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APA (6^th Edition):

Bashir, F. (2017). Hydrometeorological Variability over Pakistan . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/626357

Chicago Manual of Style (16^th Edition):

Bashir, Furrukh. “Hydrometeorological Variability over Pakistan .” 2017. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/626357.

MLA Handbook (7^th Edition):

Bashir, Furrukh. “Hydrometeorological Variability over Pakistan .” 2017. Web. 05 Mar 2021.

Vancouver:

Bashir F. Hydrometeorological Variability over Pakistan . [Internet] [Doctoral dissertation]. University of Arizona; 2017. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/626357.

Council of Science Editors:

Bashir F. Hydrometeorological Variability over Pakistan . [Doctoral Dissertation]. University of Arizona; 2017. Available from: http://hdl.handle.net/10150/626357

University of Arizona

7. Sakaguchi, Koichi. Spatiotemporal Scale Limits and Roles of Biogeochemical Cycles in Climate Predictions .

Degree: 2013, University of Arizona

URL: http://hdl.handle.net/10150/268598

► There is much confidence in the global temperature change and its attribution to human activities. Global climate models have attained unprecedented complexity in representing the… (more)

▼ There is much confidence in the global temperature change and its attribution to human activities. Global climate models have attained unprecedented complexity in representing the climate system and its response to external forcings. However, climate prediction remains a serious challenge and carries large uncertainty, particularly when the scale of interest becomes small. With the increasing interest in regional impact studies for decision-making, one of the urgent tasks is to make a systematic, quantitative evaluation of the expected skill of climate models over a range of spatiotemporal scales. The first part of this dissertation was devoted to this task, with focus on the predictive skill in the linear trend of surface air temperature. By evaluating the hindcasts for the last 120 year period in the form of deterministic and probabilistic predictions, it was found that the hindcasts can reproduce broad-scale changes in the surface air temperature, showing reliable skill at spatial scales larger than or equal to a few thousand kilometers (30° x 30°) and at temporal scales of 30 years or longer. However, their skill remains limited at smaller spatiotemporal scales, where we saw no significant improvement over climatology or a random guess. Over longer temporal scales, the feedbacks from the carbon cycle to atmospheric CO₂ concentration become important. Therefore the rest of the dissertation attempts to find key processes in the climate-carbon cycle feedback using one of the leading land-climate models, the National Center for Atmospheric Research Community Land Model. Evaluation of site-level simulations using field observations from the Amazon forest revealed that the current formulation for drought-related mortality, which lacks the ecophysiological link between short- and long-term drought stress, prevent the model from simulating realistic forest response. Global simulations showed that such dynamics of vegetation strongly influences the control of the nitrogen cycle on vegetation productivity, which then alters the sensitivity of the terrestrial biosphere to surface air temperature. This implies that if the state of the terrestrial biosphere is inconsistent with the simulated climate, either biased or prescribed, then its feedback to anthropogenic forcing could be also inconsistent. Advisors/Committee Members: Zeng, Xubin (advisor), Castro, Christopher L. (committeemember), Gupta, Hoshin V. (committeemember), Shuttleworth, W. James (committeemember), Zeng, Xubin (committeemember).

Subjects/Keywords: Carbon cycle; Climate model; Climate prediction; Atmospheric Sciences; Amazon; Atmosphere-land interaction

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APA (6^th Edition):

Sakaguchi, K. (2013). Spatiotemporal Scale Limits and Roles of Biogeochemical Cycles in Climate Predictions . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/268598

Chicago Manual of Style (16^th Edition):

Sakaguchi, Koichi. “Spatiotemporal Scale Limits and Roles of Biogeochemical Cycles in Climate Predictions .” 2013. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/268598.

MLA Handbook (7^th Edition):

Sakaguchi, Koichi. “Spatiotemporal Scale Limits and Roles of Biogeochemical Cycles in Climate Predictions .” 2013. Web. 05 Mar 2021.

Vancouver:

Sakaguchi K. Spatiotemporal Scale Limits and Roles of Biogeochemical Cycles in Climate Predictions . [Internet] [Doctoral dissertation]. University of Arizona; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/268598.

Council of Science Editors:

Sakaguchi K. Spatiotemporal Scale Limits and Roles of Biogeochemical Cycles in Climate Predictions . [Doctoral Dissertation]. University of Arizona; 2013. Available from: http://hdl.handle.net/10150/268598

University of Arizona

8. Broxton, Patrick. Improving Distributed Hydrologic Modeling and Global Land Cover Data .

Degree: 2013, University of Arizona

URL: http://hdl.handle.net/10150/307009

► Distributed models of the land surface are essential for global climate models because of the importance of land-atmosphere exchanges of water, energy, momentum. They are… (more)

▼ Distributed models of the land surface are essential for global climate models because of the importance of land-atmosphere exchanges of water, energy, momentum. They are also used for high resolution hydrologic simulation because of the need to capture non-linear responses to spatially variable inputs. Continued improvements to these models, and the data which they use, is especially important given ongoing changes in climate and land cover. In hydrologic models, important aspects are sometimes neglected due to the need to simplify the models for operational simulation. For example, operational flash flood models do not consider the role of snow and are often lumped (i.e. do not discretize a watershed into multiple units, and so do not fully consider the effect of intense, localized rainstorms). To address this deficiency, an overland flow model is coupled with a subsurface flow model to create a distributed flash flood forecasting system that can simulate flash floods that involve rain on snow. The model is intended for operational use, and there are extensive algorithms to incorporate high-resolution hydrometeorologic data, to assist in the calibration of the models, and to run the model in real time. A second study, which is designed to improve snow simulation in forested environments, demonstrates the importance of explicitly representing a near canopy environment in snow models, instead of only representing open and canopy covered areas (i.e. with % canopy fraction), as is often done. Our modeling, which uses canopy structure information from Aerial Laser Survey Mapping at 1 meter resolution, suggests that areas near trees have more net snow water input than surrounding areas because of the lack of snow interception, shading by the trees, and the effects of wind. In addition, the greatest discrepancy between our model simulations that explicitly represent forest structure and those that do not occur in areas with more canopy edges. In addition, two value-added Land Cover products (land cover type and maximum green vegetation fraction; MGVF) are developed and evaluated. The new products are good successors to current generation land cover products that are used in global models (many of which rely on 20 year old AVHRR land cover data from a single year) because they are based on 10 years of recent MODIS data. There is substantial spurious interannual variability in the MODIS land cover type data, and the MGVF product can vary substantially from year to year depending on climate conditions, suggesting the importance of using climatologies for land cover data. The new land cover type climatology also agrees better with validation sites, and the MGVF climatology is more consistent with other measures of vegetation (e.g. Leaf Area Index) than the older land cover data. Advisors/Committee Members: Troch, Peter A (advisor), Zeng, Xubin (advisor), Troch, Peter A. (committeemember), Zeng, Xubin (committeemember), Brooks, Paul D. (committeemember), Dominguez, Francina (committeemember).

Subjects/Keywords: Land Cover; LiDAR; Maximum Green Vegetation Fraction; MODIS; Snow Modeling; Hydrology; Flash Flood Modeling

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APA (6^th Edition):

Broxton, P. (2013). Improving Distributed Hydrologic Modeling and Global Land Cover Data . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/307009

Chicago Manual of Style (16^th Edition):

Broxton, Patrick. “Improving Distributed Hydrologic Modeling and Global Land Cover Data .” 2013. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/307009.

MLA Handbook (7^th Edition):

Broxton, Patrick. “Improving Distributed Hydrologic Modeling and Global Land Cover Data .” 2013. Web. 05 Mar 2021.

Vancouver:

Broxton P. Improving Distributed Hydrologic Modeling and Global Land Cover Data . [Internet] [Doctoral dissertation]. University of Arizona; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/307009.

Council of Science Editors:

Broxton P. Improving Distributed Hydrologic Modeling and Global Land Cover Data . [Doctoral Dissertation]. University of Arizona; 2013. Available from: http://hdl.handle.net/10150/307009

University of Arizona

9. Potteiger IV, Samuel Edwin. A Physically-Motivated Regression Approach to Forecasting Lake Powell Inflow .

Degree: 2020, University of Arizona

URL: http://hdl.handle.net/10150/641695

► The Colorado River provides water for a growing population in seven U.S. states and Mexico, making it undoubtedly one of the most important rivers in… (more)

Subjects/Keywords: Forecasting; Inflow; Lake Powell; Modeling; Streamflow

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APA (6^th Edition):

Potteiger IV, S. E. (2020). A Physically-Motivated Regression Approach to Forecasting Lake Powell Inflow . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/641695

Chicago Manual of Style (16^th Edition):

Potteiger IV, Samuel Edwin. “A Physically-Motivated Regression Approach to Forecasting Lake Powell Inflow .” 2020. Masters Thesis, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/641695.

MLA Handbook (7^th Edition):

Potteiger IV, Samuel Edwin. “A Physically-Motivated Regression Approach to Forecasting Lake Powell Inflow .” 2020. Web. 05 Mar 2021.

Vancouver:

Potteiger IV SE. A Physically-Motivated Regression Approach to Forecasting Lake Powell Inflow . [Internet] [Masters thesis]. University of Arizona; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/641695.

Council of Science Editors:

Potteiger IV SE. A Physically-Motivated Regression Approach to Forecasting Lake Powell Inflow . [Masters Thesis]. University of Arizona; 2020. Available from: http://hdl.handle.net/10150/641695

University of Arizona

10. Atwood, Joel Edwin. Potential Application of Cosmic-Ray Neutron Sensors to Infer Precipitation Rates .

Degree: 2019, University of Arizona

URL: http://hdl.handle.net/10150/632542

► More studies are finding utility in using cosmic-ray neutron sensors (CRNS)s to understand hydrological processes within the environment. This study explores estimating precipitation by analyzing… (more)

Subjects/Keywords: measurements; neutrons; precipitation; soil moisture

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APA (6^th Edition):

Atwood, J. E. (2019). Potential Application of Cosmic-Ray Neutron Sensors to Infer Precipitation Rates . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/632542

Chicago Manual of Style (16^th Edition):

Atwood, Joel Edwin. “Potential Application of Cosmic-Ray Neutron Sensors to Infer Precipitation Rates .” 2019. Masters Thesis, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/632542.

MLA Handbook (7^th Edition):

Atwood, Joel Edwin. “Potential Application of Cosmic-Ray Neutron Sensors to Infer Precipitation Rates .” 2019. Web. 05 Mar 2021.

Vancouver:

Atwood JE. Potential Application of Cosmic-Ray Neutron Sensors to Infer Precipitation Rates . [Internet] [Masters thesis]. University of Arizona; 2019. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/632542.

Council of Science Editors:

Atwood JE. Potential Application of Cosmic-Ray Neutron Sensors to Infer Precipitation Rates . [Masters Thesis]. University of Arizona; 2019. Available from: http://hdl.handle.net/10150/632542

University of Arizona

11. Dadashazar, Hossein. Characterization of Particle Interactions with Clouds and Precipitation Using Diverse Datasets .

Degree: 2020, University of Arizona

URL: http://hdl.handle.net/10150/641668

► The largest uncertainty in quantifying global anthropogenic radiative forcing is linked to interactions of aerosol particles with clouds (IPCC, 2013), which is partly driven by… (more)

▼ The largest uncertainty in quantifying global anthropogenic radiative forcing is linked to interactions of aerosol particles with clouds (IPCC, 2013), which is partly driven by the difficulty of conducting the required measurements and separating the influence of meteorology and aerosol pollution on clouds. The impact of aerosol particles on cloud macro/microphysical properties is challenging to address but is important for reasons extending from improving the model representation of clouds and precipitation to identifying the impacts of wet deposition on aquatic and terrestrial ecosystems due to inputs of nutrients and contaminants that may have originated from particles serving as cloud condensation nuclei (CCN) or ice nuclei (IN). In the present study, particle interactions with clouds and precipitation were investigated using diverse data sets. The results of this work are presented in the form of four studies. In the first study, sources of particles in a rural California site were identified. The interrelationships between aerosol and precipitations were investigated using data collected from co-located sampling sites. In the second study, chloride concentrations were used as a proxy for giant CCN (GCCN) concentration in low-level clouds. Using the proposed proxy, the influence of GCCN on stratocumulus cloud properties such as droplet size distribution was examined. It was shown that fixing other variables such as liquid water path, high values of sea salt led to an increase in the number of droplets with a diameter greater than 20 μm. In addition, the potential influence of giant sea salt particles on drizzle intensity was studied. In the third study, aerosol characteristics in the entrainment interface layer (EIL) were examined. The results suggest that EIL has favorable conditions for the formation of new particles. Also, it was shown that particles in the EIL have the characteristics of aerosols present in the adjacent layers including free troposphere and sub-cloud layer. In the last study, stratocumulus clearings off the U.S. West Coast were characterized. The data for the summers between 2009 and 2018 were analyzed to identify the days that clearing occurs. The average daily probability of clearing events over the summer months was about 0.3. This result demonstrates that clearings were not rare events over the Northeast Pacific. Most clearings initiated and developed near coastal topographic features such as Cape Blanco and Cape Mendocino. The spatial characteristics of clearings exhibited diurnal variability. The median lengths and area of clearings were smallest in the morning at 09:00, with an increase between 09:00 and 12:00, and then a leveling off in expansion until 18:00. Clearings have distinguishing features such as an enhanced Pacific high shifted more towards northern California, offshore air that is warm and dry, stronger coastal surface winds, enhanced lower tropospheric static stability, and increased subsidence. Gradient Boosted Regression Tree (GBRT) modeling was successfully used to… Advisors/Committee Members: Sorooshian, Armin (advisor), Betterton, Eric A. (committeemember), Zeng, Xubin (committeemember), Philipossian, Ara (committeemember).

Subjects/Keywords: Cloud clearing; Entrainment interface layer; Particle; Positive Matrix Factorization; Sea salt; Stratocumulus clouds

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dadashazar, H. (2020). Characterization of Particle Interactions with Clouds and Precipitation Using Diverse Datasets . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/641668

Chicago Manual of Style (16^th Edition):

Dadashazar, Hossein. “Characterization of Particle Interactions with Clouds and Precipitation Using Diverse Datasets .” 2020. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/641668.

MLA Handbook (7^th Edition):

Dadashazar, Hossein. “Characterization of Particle Interactions with Clouds and Precipitation Using Diverse Datasets .” 2020. Web. 05 Mar 2021.

Vancouver:

Dadashazar H. Characterization of Particle Interactions with Clouds and Precipitation Using Diverse Datasets . [Internet] [Doctoral dissertation]. University of Arizona; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/641668.

Council of Science Editors:

Dadashazar H. Characterization of Particle Interactions with Clouds and Precipitation Using Diverse Datasets . [Doctoral Dissertation]. University of Arizona; 2020. Available from: http://hdl.handle.net/10150/641668

University of Arizona

12. Reeves Eyre, James Edward Jack. Understanding Atmosphere-Ocean-Land-Ice Interactions in the Earth System .

Degree: 2020, University of Arizona

URL: http://hdl.handle.net/10150/642185

► As numerical models of the Earth system become more sophisticated – in terms of number of component models and the complexity of physical processes simulated… (more)

▼ As numerical models of the Earth system become more sophisticated – in terms of number of component models and the complexity of physical processes simulated – it becomes more difficult to understand their biases. This is especially true for near-surface quantities such as 2-meter temperature and wind speed that are influenced by interface processes. This dissertation consists of four studies that address this difficult problem. All span multiple components of the Earth system and are global in scope, making use of global observational data sets and Earth system models (ESMs). Earth system models parameterize ocean surface fluxes of heat, moisture and momentum with empirical bulk flux algorithms, which introduce biases and uncertainties into simulations. We compare, for the first time, the effects of three different algorithms in both atmosphere and ocean model simulations using E3SM. Flux differences between algorithms are larger in atmosphere simulations (where wind speeds can vary) than ocean simulations (where wind speeds are fixed by forcing data). Surface flux changes lead to global scale changes in the energy and water cycles, notably including ocean heat uptake and global mean precipitation rates. Compared to the control algorithm, both the Coupled Ocean-Atmosphere Response Experiment (COARE) and University of Arizona (UA) algorithms reduce global mean precipitation and top of atmosphere radiative biases. Ocean barrier layers (BLs) separate the mixed layer from the top of the thermocline and are able to insulate the mixed layer from entrainment of cold thermocline water. Here, we provide the first global BL assessment in three ESMs. Compared to observations, models reproduce the global distributions as semipermanent features in some tropical regions and seasonal features elsewhere. However, model BLs are generally too thin in tropical regions and too thick in higher latitudes. BL thickness biases are related to atmosphere biases in the tropics, but at higher latitudes biases are dominated by ocean circulation errors. Global and regional water cycle is a crucial component of the Earth system, and numerous studies have addressed the individual components (e.g., precipitation). Here we assess, for the first time, if remote sensing and reanalysis data sets can accurately and self consistently portray the Amazon water cycle. This is further assisted with satellite ocean salinity measurements near the mouth of the Amazon River. Ensemble means, which are widely used for individual components, are found to produce large biases in water cycle closure. Closure is achieved with only a small subset of data combinations, which rules out the lower precipitation and higher evaporation estimates. The common approach of using the Obidos stream gauge (located hundreds of kilometres from the river mouth) to represent the entire Amazon discharge is found to misrepresent the seasonal cycle, and this can affect the apparent influence of Amazon discharge on tropical Atlantic salinity. Near-surface air temperature (SAT) over… Advisors/Committee Members: Zeng, Xubin (advisor), Behrangi, Ali (committeemember), Castro, Christopher L. (committeemember), Russell, Joellen L. (committeemember).

Subjects/Keywords: Air-sea fluxes; Amazon river; Barrier layer; Climate dynamics; Earth system model; Greenland

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Reeves Eyre, J. E. J. (2020). Understanding Atmosphere-Ocean-Land-Ice Interactions in the Earth System . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/642185

Chicago Manual of Style (16^th Edition):

Reeves Eyre, James Edward Jack. “Understanding Atmosphere-Ocean-Land-Ice Interactions in the Earth System .” 2020. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/642185.

MLA Handbook (7^th Edition):

Reeves Eyre, James Edward Jack. “Understanding Atmosphere-Ocean-Land-Ice Interactions in the Earth System .” 2020. Web. 05 Mar 2021.

Vancouver:

Reeves Eyre JEJ. Understanding Atmosphere-Ocean-Land-Ice Interactions in the Earth System . [Internet] [Doctoral dissertation]. University of Arizona; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/642185.

Council of Science Editors:

Reeves Eyre JEJ. Understanding Atmosphere-Ocean-Land-Ice Interactions in the Earth System . [Doctoral Dissertation]. University of Arizona; 2020. Available from: http://hdl.handle.net/10150/642185

University of Arizona

13. Martinez Agudelo, John Alejandro. On the Hydroclimate of Southern South America: Water Vapor Transport and the Role of Shallow Groundwater on Land-Atmosphere Interactions .

Degree: 2015, University of Arizona

URL: http://hdl.handle.net/10150/595679

► The present work focuses on the sources and transport of water vapor to the La Plata Basin (LPB), and the role of groundwater dynamics on… (more)

▼ The present work focuses on the sources and transport of water vapor to the La Plata Basin (LPB), and the role of groundwater dynamics on the simulation of hydrometeorological conditions over the basin. In the first part of the study an extension to the Dynamic Recycling Model (DRM) is developed to estimate the water vapor transported to the LPB from different regions in South America and the nearby oceans, and the corresponding contribution to precipitation over the LPB. It is found that more than 23% of the precipitation over the LPB is from local origin, while nearly 20% originates from evapotranspiration from the southern Amazon. Most of the moisture comes from terrestrial sources, with the South American continent contributing more than 62% of the moisture for precipitation over the LPB. The Amazonian contribution increases during the positive phase of El Niño and the negative phase of the Antarctic Oscillation. In the second part of the study the effect of a groundwater scheme on the simulation of terrestrial water storage, soil moisture and evapotranspiration (ET) over the LPB is investigated. It is found that the groundwater scheme improves the simulation of fluctuations in the terrestrial water storage over parts of the southern Amazon. There is also an increase in the soil moisture in the root zone over those regions where the water table is closer to the surface, including parts of the western and southern Amazon, and of the central and southern LPB. ET increases in the central and southern LPB, where it is water limited. Over parts of the southeastern Amazon the effects of the groundwater scheme are only observed at higher resolution, when the convergence of lateral groundwater flow in local topographical depressions is resolved by the model. Finally, the effects of the groundwater scheme on near surface conditions and precipitation are explored. It is found that the increase in ET induced by the groundwater scheme over parts of the LPB induces an increase in near surface specific humidity, accompanied by a decrease in near surface temperature. During the dry season, downstream of the regions where ET increases, there is also a slight increase in precipitation, over a region where the model has a dry bias compared with observations. During the early rainy season, there is also an increase in the local convective available potential energy. Over the southern LPB, groundwater induces an increase in ET and precipitation of 13 and 10%, respectively. Over the LPB, the groundwater scheme tends to improve the warm and dry biases of the model. It is suggested that a more realistic simulation of the water table depth could further increase the simulated precipitation during the early rainy season. Advisors/Committee Members: Dominguez, Francina (advisor), Dominguez, Francina (committeemember), Niu, Guo-Yue (committeemember), Troch, Peter (committeemember), Zeng, Xubin (committeemember).

Subjects/Keywords: Land-atmosphere interactions; Land Surface Models; South America; Water Vapor Transport; Atmospheric Sciences; Hydrometeorology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Martinez Agudelo, J. A. (2015). On the Hydroclimate of Southern South America: Water Vapor Transport and the Role of Shallow Groundwater on Land-Atmosphere Interactions . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/595679

Chicago Manual of Style (16^th Edition):

Martinez Agudelo, John Alejandro. “On the Hydroclimate of Southern South America: Water Vapor Transport and the Role of Shallow Groundwater on Land-Atmosphere Interactions .” 2015. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/595679.

MLA Handbook (7^th Edition):

Martinez Agudelo, John Alejandro. “On the Hydroclimate of Southern South America: Water Vapor Transport and the Role of Shallow Groundwater on Land-Atmosphere Interactions .” 2015. Web. 05 Mar 2021.

Vancouver:

Martinez Agudelo JA. On the Hydroclimate of Southern South America: Water Vapor Transport and the Role of Shallow Groundwater on Land-Atmosphere Interactions . [Internet] [Doctoral dissertation]. University of Arizona; 2015. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/595679.

Council of Science Editors:

Martinez Agudelo JA. On the Hydroclimate of Southern South America: Water Vapor Transport and the Role of Shallow Groundwater on Land-Atmosphere Interactions . [Doctoral Dissertation]. University of Arizona; 2015. Available from: http://hdl.handle.net/10150/595679

University of Arizona

14. Wang, Zhen. Interactions Between Atmospheric Aerosols and Marine Boundary Layer Clouds on Regional and Global Scales .

Degree: 2018, University of Arizona

URL: http://hdl.handle.net/10150/626640

► Airborne aerosols are crucial atmospheric constituents that are involved in global climate change and human life qualities. Understanding the nature and magnitude of aerosol-cloud-precipitation interactions… (more)

▼ Airborne aerosols are crucial atmospheric constituents that are involved in global climate change and human life qualities. Understanding the nature and magnitude of aerosol-cloud-precipitation interactions is critical in model predictions for atmospheric radiation budget and the water cycle. The interactions depend on a variety of factors including aerosol physicochemical complexity, cloud types, meteorological and thermodynamic regimes and data processing techniques. This PhD work is an effort to quantify the relationships among aerosol, clouds, and precipitation on both global and regional scales by using satellite retrievals and aircraft measurements. The first study examines spatial distributions of conversion rate of cloud water to rainwater in warm maritime clouds over the globe by using NASA A-Train satellite data. This study compares the time scale of the onset of precipitation with different aerosol categories defined by values of aerosol optical depth, fine mode fraction, and Ångstrom Exponent. The results indicate that conversion time scales are actually quite sensitive to lower tropospheric static stability (LTSS) and cloud liquid water path (LWP), in addition to aerosol type. Analysis shows that tropical Pacific Ocean is dominated by the highest average conversion rate while subtropical warm cloud regions (far northeastern Pacific Ocean, far southeastern Pacific Ocean, Western Africa coastal area) exhibit the opposite result. Conversion times are mostly shorter for lower LTSS regimes. When LTSS condition is fixed, higher conversion rates coincide with higher LWP and lower aerosol index categories. After a general global view of physical property quantifications, the rest of the presented PhD studies is focused on regional airborne observations, especially bulk cloud water chemistry and aerosol aqueous-phase reactions during the summertime off the California coast. Local air mass origins are categorized into three distinct types (ocean, ships, and land) with their influences on cloud water composition examined and implications of wet deposition discussed. Chemical analysis of cloud water samples indicates a wide pH range between 2.92 and 7.58, with an average as 4.46. The highest pH values were observed north of San Francisco, coincident with the strongest land mass influence (e.g. Si, B, and Cs). Conversely, the lowest pH values were observed south of San Francisco where there is heavy ship traffic, resulting in the highest concentrations of sulfate, nitrate, V, Fe, Al, P, Cd, Ti, Sb, P, and Mn. The acidic cloud environment with influences from various air mass types can affect the California coastal aquatic ecosystem since it can promote the conversion of micronutrients to more soluble forms. Beyond characterization of how regional air mass sources affect cloud water composition, aircraft cloud water collection provides precious information on tracking cloud processing with specific species such as oxalic acid, which is the most abundant dicarboxylic acid in tropospheric aerosols. Particular attention… Advisors/Committee Members: Sorooshian, Armin (advisor), Sorooshian, Armin (committeemember), Zeng, Xubin (committeemember), Sáez, Eduardo (committeemember), Betterton, Eric A. (committeemember).

Subjects/Keywords: Aerosol; Aerosol Cloud Interactions; Aircraft; Cloud Water Chemistry; Marine Boundary Layer; Remote Sensing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wang, Z. (2018). Interactions Between Atmospheric Aerosols and Marine Boundary Layer Clouds on Regional and Global Scales . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/626640

Chicago Manual of Style (16^th Edition):

Wang, Zhen. “Interactions Between Atmospheric Aerosols and Marine Boundary Layer Clouds on Regional and Global Scales .” 2018. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/626640.

MLA Handbook (7^th Edition):

Wang, Zhen. “Interactions Between Atmospheric Aerosols and Marine Boundary Layer Clouds on Regional and Global Scales .” 2018. Web. 05 Mar 2021.

Vancouver:

Wang Z. Interactions Between Atmospheric Aerosols and Marine Boundary Layer Clouds on Regional and Global Scales . [Internet] [Doctoral dissertation]. University of Arizona; 2018. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/626640.

Council of Science Editors:

Wang Z. Interactions Between Atmospheric Aerosols and Marine Boundary Layer Clouds on Regional and Global Scales . [Doctoral Dissertation]. University of Arizona; 2018. Available from: http://hdl.handle.net/10150/626640

University of Arizona

15. Qiu, Shaoyue. Arctic Mixed-Phase Cloud Properties Using Ground-Based And Satellite Remote Sensing .

Degree: 2018, University of Arizona

URL: http://hdl.handle.net/10150/631399

► Under the influence of global climate change, the Arctic is warming at a rapid rate approximately twice the global average. Arctic clouds play important roles… (more)

▼ Under the influence of global climate change, the Arctic is warming at a rapid rate approximately twice the global average. Arctic clouds play important roles in modulating the radiation balance, and in precipitation and hydrological cycles. Among all cloud types, mixed-phase cloud, which is defined as the coexistence of liquid droplets and ice crystals in the cloud layer, is the dominant low-level cloud type over the Arctic. Different from mixed-phase cloud at lower latitudes, Arctic mixed-phase clouds (AMCs) often occur as stratiform type and can persist for hours to days and sometimes even weeks. The mechanism maintaining the AMC is not well understood; most models have problems representing the lifetime of an AMC or the phase partitioning in the cloud. There are two major objectives for this dissertation. The first one is to improve our understanding of the AMC as well as its interaction with the Arctic environment using the integrated observations available at the DOE Atmospheric Radiation Measurement (ARM) North Slope of Alaska (NSA) site. The second one is to evaluate the Clouds and the Earth’s Radiant Energy System (CERES)- the MODerate-resolution Imaging Spectroradiometer (MODIS) retrieved cloud properties at the NSA site based on the understanding of AMC properties at this site. Using the ARM merged sounding data, we find that temperature and humidity inversions exist five and eight times, respectively, more often above the AMC than below it. Furthermore, the occurrence frequency of the AMC increases with stronger humidity inversions in the cold season. This result helps to explain the persistence of AMCs even when the Arctic surface is covered by snow and ice. Then, we further investigate the interaction between different air masses with atmospheric thermodynamic properties as well as AMC properties. We find that the atmosphere is colder and drier, has lower relative humidity (RH) and is more stable under the influence of a continental type of air mass (when wind comes from south at the NSA site). AMC occurrence frequency is positively correlated with RH and negatively correlated with atmospheric stability. Therefore, the AMC occurrence frequency is 20-30% lower during a southerly wind than for other wind directions. Furthermore, AMC has a stronger precipitation process in a northerly wind than in a southerly wind. This is possibly due to the cleaner air masses from the ocean. To study Arctic cloud properties from satellite observations, we evaluate CERES- MODIS (CM) retrieved cloud properties using 10 years of ground-based observations at the ARM NSA site. The comparisons show that the CM Ed4 cloud fraction can represent the seasonal variation of cloud at the NSA site in a relative sense, but the monthly mean CF differences between CM Ed4 and ARM range from 3 to 10%. The cloud phase classification for CM Ed4 has an excellent agreement with the ground-based classification. During the daytime (solar zenith angle, SZA < 82o), the annual mean liquid (ice) CFs from ARM and CM are around 63% (16%), and… Advisors/Committee Members: Dong, Xiquan (advisor), Xi, Baike (committeemember), Minnis, Patrick (committeemember), Zeng, Xubin (committeemember), Gupta, Hoshin V. (committeemember).

Subjects/Keywords: Arctic climate; ARM NSA; atmospheric thermodynamic properties; CERES-MODIS; mixed-phase cloud; satellite cloud property retrievals

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Qiu, S. (2018). Arctic Mixed-Phase Cloud Properties Using Ground-Based And Satellite Remote Sensing . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/631399

Chicago Manual of Style (16^th Edition):

Qiu, Shaoyue. “Arctic Mixed-Phase Cloud Properties Using Ground-Based And Satellite Remote Sensing .” 2018. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/631399.

MLA Handbook (7^th Edition):

Qiu, Shaoyue. “Arctic Mixed-Phase Cloud Properties Using Ground-Based And Satellite Remote Sensing .” 2018. Web. 05 Mar 2021.

Vancouver:

Qiu S. Arctic Mixed-Phase Cloud Properties Using Ground-Based And Satellite Remote Sensing . [Internet] [Doctoral dissertation]. University of Arizona; 2018. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/631399.

Council of Science Editors:

Qiu S. Arctic Mixed-Phase Cloud Properties Using Ground-Based And Satellite Remote Sensing . [Doctoral Dissertation]. University of Arizona; 2018. Available from: http://hdl.handle.net/10150/631399

University of Arizona

16. Tang, Wenfu. Global Modeling and Analysis of Anthropogenic Combustion and Associated Emissions .

Degree: 2019, University of Arizona

URL: http://hdl.handle.net/10150/633075

► Anthropogenic combustion and associated emissions have significant impacts on air quality and climate. However, current estimates of emissions from anthropogenic combustion are still subject to… (more)

▼ Anthropogenic combustion and associated emissions have significant impacts on air quality and climate. However, current estimates of emissions from anthropogenic combustion are still subject to large uncertainties, especially in rapidly-developing regions. This hinders accurate assessments of their regional and global impacts on air quality and climate, which presents an urgent need to understand, assess, monitor, and predict anthropogenic combustion and associated emissions particularly at city-to-national scales. Combustion products co-emitted to the atmosphere and their relationships are typically related to characteristics of combustion processes. Thus, in order to understand anthropogenic combustion and associated emissions, my PhD study seeks to answer three major scientific questions: (1) To what extent could current observations of trace gases co-emitted from combustion be used to understand anthropogenic combustion, emissions, and related driving factors? (2) How well do present global climate-chemistry models simulate trace gases from combustion activities and could those models be used to study anthropogenic emissions? (3) To what extent could the current understanding of anthropogenic combustion and emissions be improved by jointly analyzing satellite, ground-based, aircraft measurements, and model simulations of trace gases co-emitted from combustion? To address the first scientific question, I combine air pollution measurements from multiple satellite instruments across 2005-2014 to characterize emergent features of the ratios of carbon monoxide (CO) and sulfate dioxide (SO2) to nitrogen dioxide (NO2) enhancements from anthropogenic emissions over 36 cities in China. The resulting emission pattern is well-correlated with economic development and traces a common emission pathway that resembles the evolution of air pollution in more developed cities. The absence of this progression in the current IPCC Representative Concentration Pathway emission inventory is most likely due to its deficient representation of the shift towards cleaner combustion in more developed cities. The results highlight the usefulness of augmenting observational capabilities by exploiting relationships of combustion tracers in constraining the temporal variation of emissions for gaseous pollutants. In addition, it is also desired to monitor and assess anthropogenic combustion and its impacts through modeling. Thus, to address the second scientific question, I evaluate simulations of two important anthropogenic combustion products (carbon dioxide (CO2) and CO) from a state-of-the-art high-resolution global prediction system, the Copernicus Atmosphere Monitoring Service (CAMS), by comparing with the Korea-United States Air Quality (KORUS-AQ) field measurements (May to June 2016) that aims to understand the factors controlling air quality over East Asia. The results show a slight overestimation for CAMS CO2 and a moderate underestimation for CAMS CO. CAMS also captures the observed more efficient combustion over Seoul compared to… Advisors/Committee Members: Arellano, Avelino F (advisor), Emmons, Louisa K. (committeemember), Zeng, Xubin (committeemember), Betterton, Eric A. (committeemember).

Subjects/Keywords: Air quality field campaigns; Anthropogenic emissions; Atmospheric chemistry modeling; KORUS-AQ; Satellite observations of atmospheric composition

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tang, W. (2019). Global Modeling and Analysis of Anthropogenic Combustion and Associated Emissions . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/633075

Chicago Manual of Style (16^th Edition):

Tang, Wenfu. “Global Modeling and Analysis of Anthropogenic Combustion and Associated Emissions .” 2019. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/633075.

MLA Handbook (7^th Edition):

Tang, Wenfu. “Global Modeling and Analysis of Anthropogenic Combustion and Associated Emissions .” 2019. Web. 05 Mar 2021.

Vancouver:

Tang W. Global Modeling and Analysis of Anthropogenic Combustion and Associated Emissions . [Internet] [Doctoral dissertation]. University of Arizona; 2019. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/633075.

Council of Science Editors:

Tang W. Global Modeling and Analysis of Anthropogenic Combustion and Associated Emissions . [Doctoral Dissertation]. University of Arizona; 2019. Available from: http://hdl.handle.net/10150/633075

University of Arizona

17. Tian, Jingjing. Cloud and Precipitation Microphysical Properties of Warm Season Mesoscale Convective Systems .

Degree: 2019, University of Arizona

URL: http://hdl.handle.net/10150/634283

► Mesoscale convective systems (MCSs) are the largest convective storms and consist of active convective towers, expansive stratiform regions, and large anvil regions. Ice melting is… (more)

▼ Mesoscale convective systems (MCSs) are the largest convective storms and consist of active convective towers, expansive stratiform regions, and large anvil regions. Ice melting is a dominant rainfall formation process in the stratiform precipitation associated with MCSs, and the vertical profiles of microphysics determine the radiation budget and redistribute energy in the atmosphere. However, the MCS cloud and precipitation microphysical properties have neither been fully understood nor characterized in models accurately. Developing targeted retrievals from long-term observations would be beneficial in understanding the cloud and precipitation microphysical properties within MCSs. There are two major objectives for this dissertation. The first one is to develop new retrieval algorithms to estimate the cloud and precipitation microphysical properties of MCSs. The second one is to make use of the new retrievals to evaluate satellite product/retrievals and improve our understanding on the spatiotemporal characteristics of warm season MCS precipitation and ice cloud microphysical properties. In our study, new retrieval algorithms are developed to estimate the MCS cloud and precipitation microphysical properties using radar measurements and some empirical relationships derived from aircraft in situ measurements during the Midlatitude Continental Convective Clouds Experiment (MC3E). The MC3E was conducted by the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) and the National Aeronautics and Space Administration (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program at the ARM Southern Great Plains (SGP) site during April-June 2011. Unique precipitation and cloud microphysical products are generated, which include the MCSs’ ice water path (IWP), liquid water path (LWP), rain water path (RLWP), vertical distributions of ice water content (IWC), and rain liquid water content and path (RLWC and RLWP) during MC3E. The retrieved vertical distributions of IWC and RLWC can help improve our understanding of the cloud-precipitation transition processes. As one application of these unique retrievals for MCSs, IWPs retrieved from satellite observations are evaluated. It is found that radar and satellite retrievals have similar probability distribution functions and small mean differences in anvil regions, however, large differences and low correlations exist in stratiform rain areas. To better understand the spatiotemporal variations of warm season MCSs’ precipitation and ice cloud microphysical properties, a new database of MCSs’ ice cloud microphysical properties has been generated during the period 2010-2012. There are different distributions of precipitation and IWP in summer and spring. Composite evolutions of MCS precipitation and IWP could be explained by the MCS stratiform precipitation formation processes during spring and summer seasons. Advisors/Committee Members: Dong, Xiquan (advisor), Xi, Baike (committeemember), Zeng, Xubin (committeemember), Williams, Christopher R. (committeemember), Gupta, Hoshin (committeemember).

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tian, J. (2019). Cloud and Precipitation Microphysical Properties of Warm Season Mesoscale Convective Systems . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/634283

Chicago Manual of Style (16^th Edition):

Tian, Jingjing. “Cloud and Precipitation Microphysical Properties of Warm Season Mesoscale Convective Systems .” 2019. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/634283.

MLA Handbook (7^th Edition):

Tian, Jingjing. “Cloud and Precipitation Microphysical Properties of Warm Season Mesoscale Convective Systems .” 2019. Web. 05 Mar 2021.

Vancouver:

Tian J. Cloud and Precipitation Microphysical Properties of Warm Season Mesoscale Convective Systems . [Internet] [Doctoral dissertation]. University of Arizona; 2019. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/634283.

Council of Science Editors:

Tian J. Cloud and Precipitation Microphysical Properties of Warm Season Mesoscale Convective Systems . [Doctoral Dissertation]. University of Arizona; 2019. Available from: http://hdl.handle.net/10150/634283

University of Arizona

18. Welty, Joshua. Land-Atmosphere Interactions Under a Moisture Transport Paradigm .

Degree: 2020, University of Arizona

URL: http://hdl.handle.net/10150/650815

► Despite extensive study over the course of many decades, land-atmosphere interactions persist as some of the more poorly-understood processes in earth system science. This deficiency… (more)

▼ Despite extensive study over the course of many decades, land-atmosphere interactions persist as some of the more poorly-understood processes in earth system science. This deficiency is largely a result of the inherent complexities of the feedbacks between surface and overlying atmosphere, as well as the effect of remote versus local influence. Additionally, there are multiple confounding factors that can further muddle the understanding of the feedback processes, such as endogeneity, persistence (autocorrelation), and seasonality of many meteorological variables. Many studies have sought to disentangle the many complicating factors, and while many have presented clear and effective conclusions, consensus remains elusive. Land-atmosphere interactions include i) atmospheric influence on land, ii) land influence on atmosphere, and iii) potential feedbacks that exist between the two, one in response to the influence of the other. Due to the strong correlation of many surface and near-surface variables (e.g. 2 m temperature and surface temperature), causality can be quite an ambiguous matter. To identify the influence of one on the other, a basic approach is to simplify the problem by isolating the behavior of certain relationships conditioned upon atmospheric state; for example, what is the relationship between antecedent soil moisture and rainfall triggering under weak atmospheric moisture convergence, and under strong atmospheric moisture convergence? By conditioning relationships on certain atmospheric moisture convergence conditions, relationships between surface and atmosphere may emerge that were previously veiled. This dissertation comprises multiple studies that address different facets of the land-atmosphere interface in relation to atmospheric moisture convergence, namely i) extreme snowmelt impact in relation to both meteorology (weather patterns, temperature, precipitation, moisture transport) and hydrology (catastrophic flooding), ii) soil moisture effects on rainfall triggering, and iii) soil moisture impact on rainfall accumulation. Overall, these endeavors show a) integrated vapor transport can be more influential in some regions compared to others regarding extreme snowmelt occurrence, b) afternoon rainfall is more likely over wetter (drier) soils when atmospheric moisture convergence is suppressed (enhanced) on a global scale, c) the soil moisture-rainfall triggering relationship is sensitive to the magnitude of the rainfall event, d) other variables must be examined in their relationship to afternoon rainfall in order to elucidate the physical pathway corresponding to a given soil moisture-rainfall relationship, and e) regionally, afternoon rainfall accumulation can be enhanced over wetter (drier) soils when atmospheric moisture transport is pronounced (limited). Regarding finding a), a machine learning technique is used to classify synoptic 500 hPa maps corresponding to extreme snowmelt events by region, which shows that snowmelt events over Sierra Nevada and Pacific Northwest are generally… Advisors/Committee Members: Zeng, Xubin (advisor), Troch, Peter (committeemember), Arellano, Avelino (committeemember), Behrangi, Ali (committeemember).

Subjects/Keywords: moisture convergence; precipitation; snowmelt; soil moisture

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APA (6^th Edition):

Welty, J. (2020). Land-Atmosphere Interactions Under a Moisture Transport Paradigm . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/650815

Chicago Manual of Style (16^th Edition):

Welty, Joshua. “Land-Atmosphere Interactions Under a Moisture Transport Paradigm .” 2020. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/650815.

MLA Handbook (7^th Edition):

Welty, Joshua. “Land-Atmosphere Interactions Under a Moisture Transport Paradigm .” 2020. Web. 05 Mar 2021.

Vancouver:

Welty J. Land-Atmosphere Interactions Under a Moisture Transport Paradigm . [Internet] [Doctoral dissertation]. University of Arizona; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/650815.

Council of Science Editors:

Welty J. Land-Atmosphere Interactions Under a Moisture Transport Paradigm . [Doctoral Dissertation]. University of Arizona; 2020. Available from: http://hdl.handle.net/10150/650815

University of Arizona

19. Stovern, Michael Kelly. Development Of A Dust Deposition Forecast Model For A Mine Tailings Impoundment .

Degree: 2014, University of Arizona

URL: http://hdl.handle.net/10150/338876

► Wind erosion, transport and deposition of particulate matter can have significant impacts on the environment. It is observed that about 40% of the global land… (more)

▼ Wind erosion, transport and deposition of particulate matter can have significant impacts on the environment. It is observed that about 40% of the global land area and 30% of the earth's population lives in semiarid environments which are especially susceptible to wind erosion and airborne transport of contaminants. With the increased desertification caused by land use changes, anthropogenic activities and projected climate change impacts windblown dust will likely become more significant. An important anthropogenic source of windblown dust in this region is associated with mining operations including tailings impoundments. Tailings are especially susceptible to erosion due to their fine grain composition, lack of vegetative coverage and high height compared to the surrounding topography. This study is focused on emissions, dispersion and deposition of windblown dust from the Iron King mine tailings in Dewey-Humboldt, Arizona, a Superfund site. The tailings impoundment is heavily contaminated with lead and arsenic and is located directly adjacent to the town of Dewey-Humboldt. The study includes in situ field measurements, computational fluid dynamic modeling and the development of a windblown dust deposition forecasting model that predicts deposition patterns of dust originating from the tailings impoundment. Two instrumented eddy flux towers were setup on the tailings impoundment to monitor the aeolian and meteorological conditions. The in situ observations were used in conjunction with a computational fluid dynamic (CFD) model to simulate the transport of windblown dust from the mine tailings to the surrounding region. The CFD model simulations include gaseous plume dispersion to simulate the transport of the fine aerosols, while individual particle transport was used to track the trajectories of larger particles and to monitor their deposition locations. The CFD simulations were used to estimate deposition of tailings dust and identify topographic mechanisms that influence deposition. Simulation results indicated that particles preferentially deposit in regions of topographic upslope. In addition, turbulent wind fields enhanced deposition in the wake region downwind of the tailings. This study also describes a deposition forecasting model (DFM) that can be used to forecast the transport and deposition of windblown dust originating from a mine tailings impoundment. The DFM uses in situ observations from the tailings and theoretical simulations of aerosol transport to parameterize the model. The model was verified through the use of inverted-disc deposition samplers. The deposition forecasting model was initialized using data from an operational Weather Research and Forecasting (WRF) model and the forecast deposition patterns were compared to the inverted-disc samples through gravimetric, chemical composition and lead isotopic analysis. The DFM was verified over several month-long observing periods by comparing transects of arsenic and lead tracers measured by the samplers to the DFM PM₂₇ forecast. Results from the… Advisors/Committee Members: Betterton, Eric A (advisor), Betterton, Eric A. (committeemember), Saez, Eduardo (committeemember), Zeng, Xubin (committeemember), Arellano, Avelino (committeemember).

Subjects/Keywords: CFD; Deposition; Superfund; Windblown dust; Aerosol; Atmospheric Sciences

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APA (6^th Edition):

Stovern, M. K. (2014). Development Of A Dust Deposition Forecast Model For A Mine Tailings Impoundment . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/338876

Chicago Manual of Style (16^th Edition):

Stovern, Michael Kelly. “Development Of A Dust Deposition Forecast Model For A Mine Tailings Impoundment .” 2014. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/338876.

MLA Handbook (7^th Edition):

Stovern, Michael Kelly. “Development Of A Dust Deposition Forecast Model For A Mine Tailings Impoundment .” 2014. Web. 05 Mar 2021.

Vancouver:

Stovern MK. Development Of A Dust Deposition Forecast Model For A Mine Tailings Impoundment . [Internet] [Doctoral dissertation]. University of Arizona; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/338876.

Council of Science Editors:

Stovern MK. Development Of A Dust Deposition Forecast Model For A Mine Tailings Impoundment . [Doctoral Dissertation]. University of Arizona; 2014. Available from: http://hdl.handle.net/10150/338876

University of Arizona

20. Stovern, Diana Rose. The Environments And Associated Physical Mechanisms That Cause Size And Structure Changes In A Tropical Cyclone .

Degree: 2014, University of Arizona

URL: http://hdl.handle.net/10150/338896

► Tropical cyclones (TCs) can make significant size changes during their lifetime. Being able to accurately forecast TC size change is important for predicting the onset… (more)

▼ Tropical cyclones (TCs) can make significant size changes during their lifetime. Being able to accurately forecast TC size change is important for predicting the onset of storm surge as well as the spatial extent of damaging winds. TC size changes can occur from internal storm dynamics, such as eyewall replacement cycle or from changes in the synoptic environment. In this study, the impacts of changing the atmospheric temperature and air-sea temperature difference on TC size and structure are investigated. The study is conducted in two parts: the first part uses the WRF-ARW model to test the sensitivity of TC size changes to simple changes in the environment; the second part to validates the results from the first part by characterizing the environments associated with real cases of TC size change in the North Atlantic basin. It is found that when the simulated atmosphere is cooled, the initial specific humidity and convective available potential energy (CAPE) decrease but the surface energy fluxes from the ocean increase. The higher surface fluxes produce a wider area of radially-inflowing air in the boundary layer, which supports a larger precipitation field and the formation of outer-core spiral rainbands. The larger precipitation field translates to a larger wind field, which is likely related to the diabatic production of potential vorticity. In contrast, when the atmosphere is warmed the surface energy fluxes reduce, which ultimately inhibits the growth of the TC wind field. The higher initial CAPE and moisture content, however, allow the TC to spin up more rapidly with a compact core of intense precipitation. Thus, it is not the temperature of the atmosphere that is causing the size changes, but instead it is the higher surface energy fluxes that arise from the increased air-sea temperature difference. Diagnostics show that fluxes of angular momentum from the environment are not responsible for the simulated TC size increases, even when the gradient in Earth vorticity is included. Rather, it is the production of energy due to the fluxes from the ocean that is responsible for the TC size increases in these simulations. Finally, a larger TC will increase in size more than a smaller TC in the same environment. In the second part of the study, the environments associated with real cases of TC size change in the North Atlantic Basin were characterized. Size changes were evaluated using the Tropical Cyclone Extended Best Track Dataset, and the environments associated with these size changes were examined using the 6-hourly, ERA-Interim global reanalysis dataset. Environmental composites show that the TCs that made size changes in the deep tropics were typically associated with more environmental, mid-level humidity and higher air-sea temperature difference. The TCs that made large size changes in the extratropics were associated with highly-baroclinic environments and high mid-level moisture south of the TC-circulation center. In general, the environments that were associated with TC size increases in the North… Advisors/Committee Members: Ritchie, Elizabeth A (advisor), Ritchie, Elizabeth A. (committeemember), Serra, Yolande (committeemember), Zeng, Xubin (committeemember), Hirschboeck, Katherine (committeemember), Moore, David (committeemember).

Subjects/Keywords: reanalysis; size; structure; tropical cyclone; WRF; environment; Atmospheric Sciences

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Stovern, D. R. (2014). The Environments And Associated Physical Mechanisms That Cause Size And Structure Changes In A Tropical Cyclone . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/338896

Chicago Manual of Style (16^th Edition):

Stovern, Diana Rose. “The Environments And Associated Physical Mechanisms That Cause Size And Structure Changes In A Tropical Cyclone .” 2014. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/338896.

MLA Handbook (7^th Edition):

Stovern, Diana Rose. “The Environments And Associated Physical Mechanisms That Cause Size And Structure Changes In A Tropical Cyclone .” 2014. Web. 05 Mar 2021.

Vancouver:

Stovern DR. The Environments And Associated Physical Mechanisms That Cause Size And Structure Changes In A Tropical Cyclone . [Internet] [Doctoral dissertation]. University of Arizona; 2014. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/338896.

Council of Science Editors:

Stovern DR. The Environments And Associated Physical Mechanisms That Cause Size And Structure Changes In A Tropical Cyclone . [Doctoral Dissertation]. University of Arizona; 2014. Available from: http://hdl.handle.net/10150/338896

21. Wang, Jingyu. Investigation of Warm Season Convective Cloud and Precipitation Properties through the Integrative Analysis of Aircraft In-situ Measurements, Ground-based Observations, and WRF Simulations .

Degree: 2018, University of Arizona

URL: http://hdl.handle.net/10150/628408

► Mesoscale convective systems (MCSs) can be separated into a precipitation portion which includes convective rain (CR) and stratiform rain (SR) and a non-precipitation canopy portion,… (more)

▼ Mesoscale convective systems (MCSs) can be separated into a precipitation portion which includes convective rain (CR) and stratiform rain (SR) and a non-precipitation canopy portion, the former dominates much of warm season (April - September) intense rainfall over the mid-latitudes, while the latter plays a significant role in the atmospheric radiation budget due to the its extensive spatial coverage. The convective rain (≥5 mm hr-1) portion features the most intense rainfall rate compared to the long-lasting stratiform rain (<5 mm hr-1) portion with large area coverage, which strongly corresponds to the high flood risk level. In order to improve the understanding of cloud-precipitation microphysical properties and their interactions for the cloud-resolving model, the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) conducted a field campaign in a collaborative effort with NASA’s Global Precipitation Measurement (GPM) mission Ground Validation (GV) program, the Midlatitude Continental Convective Clouds Experiment (MC3E), at the ARM Southern Great Plains (SGP, 36° 36' 18" N, 97° 29' 6" W) site from April to June 2011. During the MC3E field campaign, the University of North Dakota (UND) Citation II research aircraft carried out the major in situ measurements of cloud microphysical properties. By separating the MCSs into ice-phase layer and liquid-phase layer, this study investigates microphysical properties at each layer using the measurements collected by UND Citation II aircraft. For ice-phase layer, the focus is on the correction of cloud ice water content (IWC) and the reconstruction of particle size distribution (PSD) based on multiple sensors measurements. For liquid-phase layer, this study concentrates on the better parameterization of raindrop size distribution (DSD) and its application in radar-based rain rate retrieval. In addition to the investigation of MCSs’ microphysical properties, another major part of this dissertation regards the long-term statistical analysis of the warm season (April-September) precipitation over the Great Plains (GP). Specifically, two subdomains, namely the Southern Great Plains (SGP, 99.985o W to 94.985o W, 34.66o N to 38.66o N) and Northern Great Plains (NGP, 100.75o W to 95.75o W, 45o N to 49o N) are selected. By using Self-Organizing-Map (SOM) method, a total of 300 convective systems during the period 2007-2014 are objectively classified into 6 classes according to the integrative analysis of synoptic characteristics over each sub-domain respectively. Despite the difference in regional climatology, both regions demonstrate prominent seasonal contrast in dominant synoptic patterns. The early summer convective systems are more impacted by the extratropical cyclone, while the late summer/early fall events are strongly associated with subtropical ridge. Based on the SOM results, the real-time weather forecast product generated by the National Oceanic and Atmospheric Administration (NOAA) National Severe Storms Laboratory (NSSL)… Advisors/Committee Members: Dong, Xiquan (advisor), Xi, Baike (committeemember), Zeng, Xubin (committeemember), Winter, C. L. Larry (committeemember), McFarquhar, Greg M. (committeemember), Hazenberg, Pieter (committeemember).

Subjects/Keywords: Aircraft in-situ measurement; Cloud microphysics; Convective precipitation; Convective systems; Synoptic patterns; WRF evaluation

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APA (6^th Edition):

Wang, J. (2018). Investigation of Warm Season Convective Cloud and Precipitation Properties through the Integrative Analysis of Aircraft In-situ Measurements, Ground-based Observations, and WRF Simulations . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/628408

Chicago Manual of Style (16^th Edition):

Wang, Jingyu. “Investigation of Warm Season Convective Cloud and Precipitation Properties through the Integrative Analysis of Aircraft In-situ Measurements, Ground-based Observations, and WRF Simulations .” 2018. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/628408.

MLA Handbook (7^th Edition):

Wang, Jingyu. “Investigation of Warm Season Convective Cloud and Precipitation Properties through the Integrative Analysis of Aircraft In-situ Measurements, Ground-based Observations, and WRF Simulations .” 2018. Web. 05 Mar 2021.

Vancouver:

Wang J. Investigation of Warm Season Convective Cloud and Precipitation Properties through the Integrative Analysis of Aircraft In-situ Measurements, Ground-based Observations, and WRF Simulations . [Internet] [Doctoral dissertation]. University of Arizona; 2018. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/628408.

Council of Science Editors:

Wang J. Investigation of Warm Season Convective Cloud and Precipitation Properties through the Integrative Analysis of Aircraft In-situ Measurements, Ground-based Observations, and WRF Simulations . [Doctoral Dissertation]. University of Arizona; 2018. Available from: http://hdl.handle.net/10150/628408

University of Arizona

22. Wonaschuetz, Anna. Aerosol Physicochemical Properties in Relation to Meteorology: Case Studies in Urban, Marine and Arid Settings .

Degree: 2012, University of Arizona

URL: http://hdl.handle.net/10150/247258

► Atmospheric aerosols are a highly relevant component of the climate system affecting atmospheric radiative transfer and the hydrological cycle. As opposed to other key atmospheric… (more)

Subjects/Keywords: organic aerosols; shallow cumulus clouds; smelter; toxic metals; Atmospheric Sciences; aerosol particles; hygroscopic growth

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APA (6^th Edition):

Wonaschuetz, A. (2012). Aerosol Physicochemical Properties in Relation to Meteorology: Case Studies in Urban, Marine and Arid Settings . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/247258

Chicago Manual of Style (16^th Edition):

Wonaschuetz, Anna. “Aerosol Physicochemical Properties in Relation to Meteorology: Case Studies in Urban, Marine and Arid Settings .” 2012. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/247258.

MLA Handbook (7^th Edition):

Wonaschuetz, Anna. “Aerosol Physicochemical Properties in Relation to Meteorology: Case Studies in Urban, Marine and Arid Settings .” 2012. Web. 05 Mar 2021.

Vancouver:

Wonaschuetz A. Aerosol Physicochemical Properties in Relation to Meteorology: Case Studies in Urban, Marine and Arid Settings . [Internet] [Doctoral dissertation]. University of Arizona; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/247258.

Council of Science Editors:

Wonaschuetz A. Aerosol Physicochemical Properties in Relation to Meteorology: Case Studies in Urban, Marine and Arid Settings . [Doctoral Dissertation]. University of Arizona; 2012. Available from: http://hdl.handle.net/10150/247258

University of Arizona

23. Christoffersen, Bradley. The Ecohydrological Mechanisms of Resilience and Vulnerability of Amazonian Tropical Forests to Water Stress .

Degree: 2013, University of Arizona

URL: http://hdl.handle.net/10150/293566

► Predicting the interactions between climate change and ecosystems remains a core problem in global change research; tropical forest ecosystems are of particular importance because of… (more)

▼ Predicting the interactions between climate change and ecosystems remains a core problem in global change research; tropical forest ecosystems are of particular importance because of their disproportionate role in global carbon and water cycling. Amazonia is unique among tropical forest ecosystems, exhibiting a high degree of coupling with its regional hydrometeorology, such that the stability of the entire forest-climate system is dependent on the functioning of its component parts. Belowground ecohydrological interactions between soil moisture environments and the roots which permeate them initiate the water transport pathway to leaf stomata, yet despite the disproportionate role they play in vegetation-atmosphere coupling in Amazonian forest ecosystems, the impacts of climate variability on the belowground environment remain understudied. The research which follows is designed to address critical knowledge gaps in our understanding of root functioning in Amazonian tropical forests as it relates to seasonality and extremes in belowground moisture regime as well as discerning which ecohydrological mechanisms govern ecosystem-level processes of carbon and water flux. A secondary research theme is the evaluation and use of models of ecosystem function as applied to Amazonia - these models are the "knowledge boxes" which build in the ecohydrological hypotheses (some testable than others) deemed to be most important for the forest ecosystems of Amazonia. In what follows, I investigate (i) which mechanisms of water supply (from the soil environment) and water demand (by vegetation) regulate the magnitude and seasonality of evapotranspiration across broad environmental gradients of Amazonia, (ii) how specific hypotheses of root function are or are not corroborated by soil moisture measurements conducted under normal seasonal and experimentally-induced extreme drought conditions, and (iii) the linkage between an extreme drought event with associated impacts on root zone soil moisture, the inferred response of root water uptake, and the observed impacts on ecosystem carbon and water flux in an east central Amazonian forest. Advisors/Committee Members: Saleska, Scott R (advisor), Enquist, Brian J. (committeemember), Huxman, Travis E. (committeemember), Zeng, Xubin (committeemember), Ferré, Paul A. (committeemember), Saleska, Scott R. (committeemember).

Subjects/Keywords: ecosystem land surface models; eddy covariance; plant water relations; root dynamics; tropical forests; Ecology & Evolutionary Biology; Amazonia

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APA (6^th Edition):

Christoffersen, B. (2013). The Ecohydrological Mechanisms of Resilience and Vulnerability of Amazonian Tropical Forests to Water Stress . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/293566

Chicago Manual of Style (16^th Edition):

Christoffersen, Bradley. “The Ecohydrological Mechanisms of Resilience and Vulnerability of Amazonian Tropical Forests to Water Stress .” 2013. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/293566.

MLA Handbook (7^th Edition):

Christoffersen, Bradley. “The Ecohydrological Mechanisms of Resilience and Vulnerability of Amazonian Tropical Forests to Water Stress .” 2013. Web. 05 Mar 2021.

Vancouver:

Christoffersen B. The Ecohydrological Mechanisms of Resilience and Vulnerability of Amazonian Tropical Forests to Water Stress . [Internet] [Doctoral dissertation]. University of Arizona; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/293566.

Council of Science Editors:

Christoffersen B. The Ecohydrological Mechanisms of Resilience and Vulnerability of Amazonian Tropical Forests to Water Stress . [Doctoral Dissertation]. University of Arizona; 2013. Available from: http://hdl.handle.net/10150/293566

University of Arizona

24. Sanchez-Mejia, Zulia Mayari. Monsoon Dependent Ecosystems: Implications of the Vertical Distribution of Soil Moisture on Land Surface-Atmosphere Interactions .

Degree: 2013, University of Arizona

URL: http://hdl.handle.net/10150/299116

► Uncertainty of predicted change in precipitation frequency and intensity motivates the scientific community to better understand, quantify, and model the possible outcome of dryland ecosystems.… (more)

▼ Uncertainty of predicted change in precipitation frequency and intensity motivates the scientific community to better understand, quantify, and model the possible outcome of dryland ecosystems. In pulse dependent ecosystems (i.e. monsoon driven) soil moisture is tightly linked to atmospheric processes. Here, I analyze three overarching questions; Q1) How does soil moisture presence or absence in a shallow or deep layer influence the surface energy budget and planetary boundary layer characteristics?, Q2) What is the role of vegetation on ecosystem albedo in the presence or absence of deep soil moisture?, Q3) Can we develop empirical relationships between soil moisture and the planetary boundary layer height to help evaluate the role of future precipitation changes in land surface atmosphere interactions?. To address these questions I use a conceptual framework based on the presence or absence of soil moisture in a shallow or deep layer. I define these layers by using root profiles and establish soil moisture thresholds for each layer using four years of observations from the Santa Rita Creosote Ameriflux site. Soil moisture drydown curves were used to establish the shallow layer threshold in the shallow layer, while NEE (Net Ecosystem Exchange of carbon dioxide) was used to define the deep soil moisture threshold. Four cases were generated using these thresholds: Case 1, dry shallow layer and dry deep layer; Case 2, wet shallow layer and dry deep layer; Case 3, wet shallow layer and wet deep layer, and Case 4 dry shallow and wet deep layer. Using this framework, I related data from the Ameriflux site SRC (Santa Rita Creosote) from 2008 to 2012 and from atmospheric soundings from the nearby Tucson Airport; conducted field campaigns during 2011 and 2012 to measure albedo from individual bare and canopy patches that were then evaluated in a grid to estimate the influence of deep moisture on albedo via vegetation cover change; and evaluated the potential of using a two-layer bucket model and empirical relationships to evaluate the link between deep soil moisture and the planetary boundary layer height under changing precipitation regime. My results indicate that (1) the presence or absence of water in two layers plays a role in surface energy dynamics, (2) soil moisture presence in the deep layer is linked with decreased ecosystem albedo and planetary boundary layer height, (3) deep moisture sustains vegetation greenness and decreases albedo, and (4) empirical relationships are useful in modeling planetary boundary layer height from dryland ecosystems. Based on these results we argue that deep soil moisture plays an important role in land surface-atmosphere interactions. Advisors/Committee Members: Papuga, Shirley A (advisor), Dominguez, Francina (committeemember), Zeng, Xubin (committeemember), Archer, Steve (committeemember), van Leeuwen, Willem (committeemember), Papuga, Shirley A. (committeemember).

Subjects/Keywords: creosote bush; eddy covariance; land surface - atmosphere interactions; Larrea tridentata; Santa Rita Experimental Range; Natural Resources; albedo

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APA (6^th Edition):

Sanchez-Mejia, Z. M. (2013). Monsoon Dependent Ecosystems: Implications of the Vertical Distribution of Soil Moisture on Land Surface-Atmosphere Interactions . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/299116

Chicago Manual of Style (16^th Edition):

Sanchez-Mejia, Zulia Mayari. “Monsoon Dependent Ecosystems: Implications of the Vertical Distribution of Soil Moisture on Land Surface-Atmosphere Interactions .” 2013. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/299116.

MLA Handbook (7^th Edition):

Sanchez-Mejia, Zulia Mayari. “Monsoon Dependent Ecosystems: Implications of the Vertical Distribution of Soil Moisture on Land Surface-Atmosphere Interactions .” 2013. Web. 05 Mar 2021.

Vancouver:

Sanchez-Mejia ZM. Monsoon Dependent Ecosystems: Implications of the Vertical Distribution of Soil Moisture on Land Surface-Atmosphere Interactions . [Internet] [Doctoral dissertation]. University of Arizona; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/299116.

Council of Science Editors:

Sanchez-Mejia ZM. Monsoon Dependent Ecosystems: Implications of the Vertical Distribution of Soil Moisture on Land Surface-Atmosphere Interactions . [Doctoral Dissertation]. University of Arizona; 2013. Available from: http://hdl.handle.net/10150/299116

25. Stillman, Susan. Terrestrial Precipitation and Soil Moisture: A Case Study over Southern Arizona and Data Development .

Degree: 2016, University of Arizona

URL: http://hdl.handle.net/10150/621434

► Quantifying climatological precipitation and soil moisture as well as interannual variability and trends requires extensive observation. This work focuses on the analysis of available precipitation… (more)

▼ Quantifying climatological precipitation and soil moisture as well as interannual variability and trends requires extensive observation. This work focuses on the analysis of available precipitation and soil moisture data and the development of new ways to estimate these quantities. Precipitation and soil moisture characteristics are highly dependent on the spatial and temporal scales. We begin at the point scale, examining hourly precipitation and soil moisture at individual gauges. First, we focus on the Walnut Gulch Experimental Watershed (WGEW), a 150 km² area in southern Arizona. The watershed has been measuring rainfall since 1956 with a very high density network of approximately 0.6 gauges per km². Additionally, there are 19 soil moisture probes at 5 cm depth with data starting in 2002. In order to extend the measurement period, we have developed a water balance model which estimates monsoon season (Jul-Sep) soil moisture using only precipitation for input, and calibrated so that the modeled soil moisture fits best with the soil moisture measured by each of the 19 probes from 2002-2012. This observationally constrained soil moisture is highly correlated with the collocated probes (R=0.88), and extends the measurement period from 10 to 56 years and the number of gauges from 19 to 88. Then, we focus on the spatiotemporal variability within the watershed and the ability to estimate area averaged quantities. Spatially averaged precipitation and observationally constrained soil moisture from the 88 gauges is then used to evaluate various gridded datasets. We find that gauge-based precipitation products perform best followed by reanalyses and then satellite-based products. Coupled Model Intercomparison Project Phase 5 (CMIP5) models perform the worst and overestimate cold season precipitation while offsetting the monsoon peak precipitation forward or backward by a month. Satellite-based soil moisture is the best followed by land data assimilation systems and reanalyses. We show that while WGEW is small compared to the grid size of many of the evaluated products, unlike scaling from point to area, the effect of scaling from smaller to larger area is small. Finally, we focus on global precipitation. Global monthly gauge based precipitation data has become widely available in recent years and is necessary for analyzing the climatological and anomaly precipitation fields as well as for calibrating and evaluating other gridded products such as satellite-based and modeled precipitation. However, frequency and intensity of precipitation are also important in the partitioning of water and energy fluxes. Therefore, because daily and sub-daily observed precipitation is limited to recent years, the number of raining days per month (N) is needed. We show that the only currently available long-term N product, developed by the Climate Research Unit (CRU), is deficient in certain areas, particularly where CRU gauge data is sparse. We then develop a new global 110-year N product, which shows significant improvement over CRU using… Advisors/Committee Members: Zeng, Xubin (advisor), Zeng, Xubin (committeemember), Dominguez, Francina (committeemember), Niu, Guo-Yue (committeemember), Troch, Peter (committeemember).

Subjects/Keywords: Precipitation; Soil Moisture; Hydrometeorology; Hydrology

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APA (6^th Edition):

Stillman, S. (2016). Terrestrial Precipitation and Soil Moisture: A Case Study over Southern Arizona and Data Development . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/621434

Chicago Manual of Style (16^th Edition):

Stillman, Susan. “Terrestrial Precipitation and Soil Moisture: A Case Study over Southern Arizona and Data Development .” 2016. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/621434.

MLA Handbook (7^th Edition):

Stillman, Susan. “Terrestrial Precipitation and Soil Moisture: A Case Study over Southern Arizona and Data Development .” 2016. Web. 05 Mar 2021.

Vancouver:

Stillman S. Terrestrial Precipitation and Soil Moisture: A Case Study over Southern Arizona and Data Development . [Internet] [Doctoral dissertation]. University of Arizona; 2016. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/621434.

Council of Science Editors:

Stillman S. Terrestrial Precipitation and Soil Moisture: A Case Study over Southern Arizona and Data Development . [Doctoral Dissertation]. University of Arizona; 2016. Available from: http://hdl.handle.net/10150/621434

26. Geil, Kerrie L. Assessing the 20th Century Performance of Global Climate Models and Application to Climate Change Adaptation Planning .

Degree: 2017, University of Arizona

URL: http://hdl.handle.net/10150/623015

► Rapid environmental changes linked to human-induced increases in atmospheric greenhouse gas concentrations have been observed on a global scale over recent decades. Given the relative… (more)

▼ Rapid environmental changes linked to human-induced increases in atmospheric greenhouse gas concentrations have been observed on a global scale over recent decades. Given the relative certainty of continued change across many earth systems, the information output from climate models is an essential resource for adaptation planning. But in the face of many known modeling deficiencies, how confident can we be in model projections of future climate? It stands to reason that a realistic simulation of the present climate is at least a necessary (but likely not sufficient) requirement for a model’s ability to realistically simulate the climate of the future. Here, I present the results of three studies that evaluate the 20th century performance of global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5). The first study examines precipitation, geopotential height, and wind fields from 21 CMIP5 models to determine how well the North American monsoon system (NAMS) is simulated. Models that best capture large-scale circulation patterns at low levels usually have realistic representations of the NAMS, but even the best models poorly represent monsoon retreat. Difficulty in reproducing monsoon retreat results from an inaccurate representation of gradients in low-level geopotential height across the larger region, which causes an unrealistic flux of low-level moisture from the tropics into the NAMS region that extends well into the post-monsoon season. The second study examines the presence and severity of spurious Gibbs-type numerical oscillations across the CMIP5 suite of climate models. The oscillations can appear as unrealistic spatial waves near discontinuities or sharp gradients in global model fields (e.g., orography) and have been a known problem for decades. Multiple methods of oscillation reduction exist; consequently, the oscillations are presumed small in modern climate models and hence are rarely addressed in recent literature. Here we quantify the oscillations in 13 variables from 48 global climate models along a Pacific ocean transect near the Andes. Results show that 48% of nonspectral models and 95% of spectral models have at least one variable with oscillation amplitude as large as, or greater than, atmospheric interannual variability. The third study is an in-depth assessment model simulations of 20th century monthly minimum and maximum surface air temperature over eight US regions, using mean state, trend, and variability bias metrics. Transparent model performance information is provided in the form of model rankings for each bias type. A wide range in model skill is at the regional scale, but no strong relationships are seen between any of the three bias types or between 20th century bias and 21st century projected change. Using our model rankings, two smaller ensembles of models with better performance over the southwestern U.S. are selected, but they result in negligible differences from the all-model ensemble in the average 21st century projected temperature change and… Advisors/Committee Members: Zeng, Xubin (advisor), Zeng, Xubin (committeemember), Crimmins, Michael (committeemember), Ferguson, Daniel (committeemember), Marsh, Stuart (committeemember).

Subjects/Keywords: Climate Change Resilience Planning; Climate Models; Connecting Science and Decision Making; Modeling Error; North American Monsoon; Applied Climate Science

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APA (6^th Edition):

Geil, K. L. (2017). Assessing the 20th Century Performance of Global Climate Models and Application to Climate Change Adaptation Planning . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/623015

Chicago Manual of Style (16^th Edition):

Geil, Kerrie L. “Assessing the 20th Century Performance of Global Climate Models and Application to Climate Change Adaptation Planning .” 2017. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/623015.

MLA Handbook (7^th Edition):

Geil, Kerrie L. “Assessing the 20th Century Performance of Global Climate Models and Application to Climate Change Adaptation Planning .” 2017. Web. 05 Mar 2021.

Vancouver:

Geil KL. Assessing the 20th Century Performance of Global Climate Models and Application to Climate Change Adaptation Planning . [Internet] [Doctoral dissertation]. University of Arizona; 2017. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/623015.

Council of Science Editors:

Geil KL. Assessing the 20th Century Performance of Global Climate Models and Application to Climate Change Adaptation Planning . [Doctoral Dissertation]. University of Arizona; 2017. Available from: http://hdl.handle.net/10150/623015

27. Yang, Zhao. Land-Atmosphere Interactions Due to Anthropogenic and Natural Changes in the Land Surface: A Numerical Modeling .

Degree: 2017, University of Arizona

URL: http://hdl.handle.net/10150/623069

► Alterations to the land surface can be attributed to both human activity and natural variability. Human activities, such as urbanization and irrigation, can change the… (more)

▼ Alterations to the land surface can be attributed to both human activity and natural variability. Human activities, such as urbanization and irrigation, can change the conditions of the land surface by altering albedo, soil moisture, aerodynamic roughness length, the partitioning of net radiation into sensible and latent heat, and other surface characteristics. On the other hand, natural variability, manifested through changes in atmospheric circulation, can also induce land surface changes. These regional scale land surface changes, induced either by humans or natural variability, can effectively modify atmospheric conditions through land-atmosphere interactions. However, only in recent decades have numerical models begun to include representations of the critical processes driving changes at the land surface, and their associated effects on the overlying atmosphere. In this work we explore three mechanisms by which changes to the land surface–both anthropogenic and naturally induced–impact the overlying atmosphere and affect regional hydroclimate. The first land-atmosphere interaction mechanism explored here is land-use and land-cover change (LULCC) due to urban expansion. Such changes alter the surface albedo, heat capacity, and thermal conductivity of the surface. Consequently, the energy balance in urban regions is different from that of natural surfaces. To evaluate the changes in regional hydroclimate that could arise due to projected urbanization in the Phoenix–Tucson corridor, Arizona, my first study applied the Weather Research and Forecasting (WRF) with an Urban Canopy Model (UCM; which includes a detailed urban radiation scheme) coupled to the Noah land surface model to this region. Land-cover changes were represented using land-cover data for 2005 and projections to 2050, and historical North American Regional Reanalysis (NARR) data were used to specify the lateral boundary conditions. Results suggest that temperature changes are well defined, reflecting the urban heat island (UHI) effect within areas experiencing LULCC, whereas changes in precipitation are less certain (statistically less robust). However, the study indicates the likelihood of reductions in precipitation over the mountainous regions northeast of Phoenix and decreased evening precipitation over the newly urbanized area. The second land-atmosphere interaction mechanism explored here is irrigation which, while being an important anthropogenic factor affecting the local to regional water cycle, is not typically represented in regional climate models. In this (second) study, I incorporated an irrigation scheme into the Noah land surface scheme coupled to the WRF model. Using a newly developed water vapor tracer package (developed by Miguez-Macho et al. 2013), the study tracks the path of water vapor that evapotranspires from the irrigated regions. To assess the impact of irrigation over the California Central Valley (CCV) on the regional climate of the U.S. Southwest, I ran six simulations (for three dry and three wet years), both with and… Advisors/Committee Members: Zeng, Xubin (advisor), Zeng, Xubin (committeemember), Dominguez, Francina (committeemember), Niu, Guo-Yue (committeemember).

Subjects/Keywords: human impact; irrigation; land use change; regional climate modeling; heat wave

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APA (6^th Edition):

Yang, Z. (2017). Land-Atmosphere Interactions Due to Anthropogenic and Natural Changes in the Land Surface: A Numerical Modeling . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/623069

Chicago Manual of Style (16^th Edition):

Yang, Zhao. “Land-Atmosphere Interactions Due to Anthropogenic and Natural Changes in the Land Surface: A Numerical Modeling .” 2017. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/623069.

MLA Handbook (7^th Edition):

Yang, Zhao. “Land-Atmosphere Interactions Due to Anthropogenic and Natural Changes in the Land Surface: A Numerical Modeling .” 2017. Web. 05 Mar 2021.

Vancouver:

Yang Z. Land-Atmosphere Interactions Due to Anthropogenic and Natural Changes in the Land Surface: A Numerical Modeling . [Internet] [Doctoral dissertation]. University of Arizona; 2017. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/623069.

Council of Science Editors:

Yang Z. Land-Atmosphere Interactions Due to Anthropogenic and Natural Changes in the Land Surface: A Numerical Modeling . [Doctoral Dissertation]. University of Arizona; 2017. Available from: http://hdl.handle.net/10150/623069

28. Bashir, Furrukh. Quantified Assessment of the Meteorological Variables Facilitating the Establishment of the Karakoram Anomaly .

Degree: 2016, University of Arizona

URL: http://hdl.handle.net/10150/622832

► Lofty Hindukush, Karakoram and Himalayan (HKH) mountain ranges centered in the Northern Pakistan are host to some of the world’s largest glaciers outside the Polar… (more)

▼ Lofty Hindukush, Karakoram and Himalayan (HKH) mountain ranges centered in the Northern Pakistan are host to some of the world’s largest glaciers outside the Polar Regions and are a source of water for drinking and irrigation to the millions of people living downstream. With the increase in the global temperatures, glaciers are reported as retreating globally. However, some of the glaciers in the Karakoram mountain ranges are reported as surging with positive mass balance, especially since the 1990s. This phenomenon is described as "The Karakoram Anomaly". Various efforts have been made to explain the state and fate of the HKH glaciers in the recent past. However, they are limited to quantification of the change in temperature, precipitation and river runoff, or through their impact on future climate projections. For the HKH region, temperature fluctuations have been out of the phase with hemispheric trends for past several centuries. Therefore, climate change in this region is not solely the temperature effect on melting as compared to other glaciated regions. To identify the reasons for the establishment of the Karakoram Anomaly, monthly mean climatic variables for last five decades, reported from meteorological observatories at the valley floors in HKH region, are analyzed. In addition to the climatic variables of temperature and precipitation, monthly mean synoptic observations reported by meteorological observatories in both morning and afternoon, along with monthly mean radiosonde data are used. From these data the role of different near-surface and upper atmospheric meteorological variables in maintaining the positive mass balance of the glaciers and the development of the Karakoram Anomaly can be explained. An overall warming in the region is observed. The trends in the summer temperatures, which were reported as decreasing a decade ago, are now found as increasing in updated time series. However, the overall gradient is still negative. The winter mean and maximum temperatures are increasing with accelerated trends. Both maximum and minimum temperatures in summer are not diverging anymore and the diurnal temperature range is decreasing in the most recent decade. The afternoon cloudiness is found as increasing throughout the year except for spring, which is indicative of an increase in convective uplifting. Moreover, humidity is increasing all over the region; due to evaporation in the spring, from monsoon moisture advection in summer, and due to the recycling of monsoon moisture in autumn. Furthermore, near-surface wind speed and net radiation in the region are decreasing, explaining the decrease in the summer minimum temperature and the presence of the cloudy skies. The decrease in near-surface wind speed, and net radiation, and increase in water vapor pressure put a limit on the evapotranspiration process. In addition, winter and summer precipitation is increasing. The aridity index, which is based on the ratio of precipitation and reference evaporation, indicates that region is turning moisture surplus and… Advisors/Committee Members: Gupta, Hoshin V (advisor), Gupta, Hoshin V. (committeemember), Zeng, Xubin (committeemember), Hazenberg, Pieter (committeemember).

Subjects/Keywords: Climate Change; Glaciers; Global Warming; Positive Mass Balance; The Karakoram Anomaly; Upper Indus Basin

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APA (6^th Edition):

Bashir, F. (2016). Quantified Assessment of the Meteorological Variables Facilitating the Establishment of the Karakoram Anomaly . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/622832

Chicago Manual of Style (16^th Edition):

Bashir, Furrukh. “Quantified Assessment of the Meteorological Variables Facilitating the Establishment of the Karakoram Anomaly .” 2016. Masters Thesis, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/622832.

MLA Handbook (7^th Edition):

Bashir, Furrukh. “Quantified Assessment of the Meteorological Variables Facilitating the Establishment of the Karakoram Anomaly .” 2016. Web. 05 Mar 2021.

Vancouver:

Bashir F. Quantified Assessment of the Meteorological Variables Facilitating the Establishment of the Karakoram Anomaly . [Internet] [Masters thesis]. University of Arizona; 2016. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/622832.

Council of Science Editors:

Bashir F. Quantified Assessment of the Meteorological Variables Facilitating the Establishment of the Karakoram Anomaly . [Masters Thesis]. University of Arizona; 2016. Available from: http://hdl.handle.net/10150/622832

29. Chrisman, Bobby Brady. Quantifying Mesoscale Soil Moisture with the Cosmic-Ray Rover .

Degree: 2013, University of Arizona

URL: http://hdl.handle.net/10150/293622

► Existing techniques measure soil moisture either at a point or over a large area many kilometers across. To bridge these two scales, we used the… (more)

Subjects/Keywords: COSMOS; Hydrology; Remote Sensing; Soil Moisture; Upscaling; Cosmic-Ray Rover

…the University of Arizona Graduate College’s Manual for Electronic Theses and Dissertations… …Water Resources University of Arizona, Tucson AZ Correspondence to B.B. Chrisman (… …particular, for stops near the University of Arizona where the soil is wetter, and Sentinel Hill… …to irregular irrigation, and for the anomalously wet University of Arizona and anomalously…

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APA (6^th Edition):

Chrisman, B. B. (2013). Quantifying Mesoscale Soil Moisture with the Cosmic-Ray Rover . (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/293622

Chicago Manual of Style (16^th Edition):

Chrisman, Bobby Brady. “Quantifying Mesoscale Soil Moisture with the Cosmic-Ray Rover .” 2013. Masters Thesis, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/293622.

MLA Handbook (7^th Edition):

Chrisman, Bobby Brady. “Quantifying Mesoscale Soil Moisture with the Cosmic-Ray Rover .” 2013. Web. 05 Mar 2021.

Vancouver:

Chrisman BB. Quantifying Mesoscale Soil Moisture with the Cosmic-Ray Rover . [Internet] [Masters thesis]. University of Arizona; 2013. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/293622.

Council of Science Editors:

Chrisman BB. Quantifying Mesoscale Soil Moisture with the Cosmic-Ray Rover . [Masters Thesis]. University of Arizona; 2013. Available from: http://hdl.handle.net/10150/293622

30. Crosbie, Ewan Colin. Aerosol and Gas-phase Characteristics in Relation to Meteorology: Case Studies in Populated Arid Settings .

Degree: 2015, University of Arizona

URL: http://hdl.handle.net/10150/560618

► Atmospheric aerosols and trace gases are a highly relevant component of the climate system affecting atmospheric radiative transfer and the hydrologic cycle. In arid and… (more)

▼ Atmospheric aerosols and trace gases are a highly relevant component of the climate system affecting atmospheric radiative transfer and the hydrologic cycle. In arid and semi-arid regions, where cloud cover is often low and precipitation is generally scarce and sporadic, the driving processes accounting for the production, loss and transport of atmospheric constituents are often distinctly different from other climates. In arid regions, the same circulation dynamics that suppress cloud formation can be responsible for creating strong subsidence inversions, which cap atmospheric mixing and trap pollutants close to the surface, often placing populated arid regions high on global rankings of air pollution concerns. In addition, low soil moisture can encourage wind-blown dust emissions, which can be a significant fraction of the total aerosol loading in both coarse and fine modes on a mass basis. Three distinct focus regions are investigated over varying time scales, using a diverse set of techniques, and with wide-ranging primary goals. 1) the Tehran metropolitan area in Iran over a ten-year period from 2000-2009, 2) Tucson, Arizona over 2012-2014 with three intensive monitoring periods during summer 2014 and winter 2015 and 3) the San Joaquin Valley in California during the NASA DISCOVER-AQ campaign during Jan-Feb 2013. However, in all cases, local and regional scale meteorology play a significant role in controlling the spatiotemporal variability in trace gas and aerosol concentrations. Particular emphasis is placed on understanding transport pathways due to the local wind patterns and the importance of key meteorological parameters such as temperature, humidity and solar radiation on controlling production and loss mechanisms. While low in magnitude, the precipitation pattern is still an important sink mechanism that modulates gas phase and particle abundances in all three regions, either through scavenging or by promoting vertical mixing. The reported measurements and data analysis serve to improve the characterization of trace gases and aerosols in populated arid regions and offer process level understanding of dominant mechanisms for model validations and improvements. Advisors/Committee Members: Sorooshian, Armin (advisor), Betterton, Eric (committeemember), Zeng, Xubin (committeemember), Sorooshian, Armin (committeemember).

Subjects/Keywords: Atmospheric Sciences

…took place at a rooftop site at the University of Arizona from 2012 to 2014. Long-term… …Taylor Shingler b, Omid Esmaili c a. Department of Atmospheric Sciences, University of Arizona… …University of Arizona, Tucson, AZ 85721, USA; E-Mail: [email protected] Department of Chemical… …and Environmental Engineering, University of Arizona, Tucson, AZ 85721, USA; E-Mails… …was centered around ground based in situ aerosol measurements made at the University of…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Crosbie, E. C. (2015). Aerosol and Gas-phase Characteristics in Relation to Meteorology: Case Studies in Populated Arid Settings . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/560618

Chicago Manual of Style (16^th Edition):

Crosbie, Ewan Colin. “Aerosol and Gas-phase Characteristics in Relation to Meteorology: Case Studies in Populated Arid Settings .” 2015. Doctoral Dissertation, University of Arizona. Accessed March 05, 2021. http://hdl.handle.net/10150/560618.

MLA Handbook (7^th Edition):

Crosbie, Ewan Colin. “Aerosol and Gas-phase Characteristics in Relation to Meteorology: Case Studies in Populated Arid Settings .” 2015. Web. 05 Mar 2021.

Vancouver:

Crosbie EC. Aerosol and Gas-phase Characteristics in Relation to Meteorology: Case Studies in Populated Arid Settings . [Internet] [Doctoral dissertation]. University of Arizona; 2015. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10150/560618.

Council of Science Editors:

Crosbie EC. Aerosol and Gas-phase Characteristics in Relation to Meteorology: Case Studies in Populated Arid Settings . [Doctoral Dissertation]. University of Arizona; 2015. Available from: http://hdl.handle.net/10150/560618

Open Access Theses and Dissertations