+publisher:"Texas A&M University" +contributor:("Saravanan, Ramalingam")

Texas A&M University

1. Liu, Xue. Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics.

Degree: PhD, Oceanography, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/173790

► As resolution of observations and climate models continues to improve, it has become increasingly evident that mesoscale eddies – a ubiquitous feature of the world… (more)

▼ As resolution of observations and climate models continues to improve, it has become increasingly evident that mesoscale eddies – a ubiquitous feature of the world ocean – can interact with the overlying atmosphere, potentially affecting large-scale atmospheric and oceanic circulation and climate. Improving our understanding of this ocean mesoscale eddy – atmosphere (OME-A) interaction has important implications for improving climate simulations and predictions. This dissertation contributes to this understanding by focusing on two elements of OME-A interaction. The first element deals with the influence of ocean mesoscale eddies on rainfall. By comparing three different satellite-derived rainfall datasets, we examined the robustness of the rainfall response to ocean eddy induced mesoscale sea-surface temperature anomalies (SSTAs). The three datasets are the Tropical Rainfall Measurement Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA), NOAA Climate Prediction Center (CPC) Morphing Technique (CMORPH) global precipitation and newly available Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) that is based on the latest remote sensing technology with finer spatial and temporal resolution. The results show that 1) all datasets exhibit a similar rainfall response to ocean eddies, but the amplitude of the rainfall response varies among datasets with IMERG producing the strongest and most coherent rainfall response, despite the weakest time-mean rainfall, 2) eddy-induced precipitation response is significantly stronger in winter than in summer and over warm eddies than cold eddies, and these asymmetries in rainfall response is more robust in IMERG than in the other two datasets. Documenting and analyzing these asymmetric rainfall responses are important for understanding the potential role of ocean eddies in forcing the large-scale atmospheric circulation and climate. The second element examines the effect of OME-A interaction on ocean eddy wind power that plays a vital role in dissipating eddy kinetic energy (EKE). By using a scaling analysis and analyzing eddy-resolving coupled climate model simulations, we not only quantify the impact of OME-A interaction on eddy wind power, but also provide a mechanistic understanding of the underlying process. Results show that the impact of OME-A feedback on eddy wind power, albeit smaller than that due to ocean current feedback, is significant and amounts to about 30-40% reduction of the value without OME-A interaction. Therefore, in the absence of OME-A interaction, eddy wind power is significantly overestimated, thus providing a too-strong sink for EKE. Advisors/Committee Members: Chang, Ping (advisor), Lin, Xiaopei (advisor), Saravanan, Ramalingam (committee member), Szunyogh, Istvan (committee member).

Subjects/Keywords: Oceanic Mesoscale Eddies; Air-Sea Interaction; Rainfall; Wind Power

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APA (6^th Edition):

Liu, X. (2018). Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/173790

Chicago Manual of Style (16^th Edition):

Liu, Xue. “Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics.” 2018. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/173790.

MLA Handbook (7^th Edition):

Liu, Xue. “Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics.” 2018. Web. 16 Jan 2021.

Vancouver:

Liu X. Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/173790.

Council of Science Editors:

Liu X. Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/173790

Texas A&M University

2. Jing, Zhao. A Study of Interactions Between Near-inertial Internal Waves and Mesoscale-to-Submesoscale Flows.

Degree: PhD, Oceanography, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/156997

► In this dissertation, we explore interactions between near-inertial internal waves (NIWs) and mesoscale-to-submesoscale flows. Three different topics under this broad subject are investigated using theoretical,… (more)

▼ In this dissertation, we explore interactions between near-inertial internal waves (NIWs) and mesoscale-to-submesoscale flows. Three different topics under this broad subject are investigated using theoretical, numerical and observational approaches. The downward radiation of NIWs from the mixed layer to deep ocean in an idealized baroclinic geostrophic flow is theoretically analyzed based on the Young-Ben Jelloul (YBJ) equation. It is found that the dispersion of NIWs in the presence of baroclinic flow is achieved mainly through the phase separation among different horizontal and vertical modes. Both the eigen-frequency differences and mode-mode interferences contribute to the phase separation with the interferences locally in the modal space playing a much more dominant role than the nonlocal mode-mode interferences. Data from long-term mooring array and high-resolution numerical simulations in the Gulf of Mexico are used to analyze energy exchange between near-inertial internal waves and mesoscale eddies. Both the observations and numerical simulations reveal a permanent energy transfer from mesoscale eddies to NIWs below the mixed layer. In particular, this permanent energy transfer mainly occurs when the Okubo-Weiss (OW) parameter is positive. Further analysis suggests that the wave capture mechanism plays a key role in interactions between NIWs and mesoscale eddies. NIWs become highly anisotropic when the OW parameter is positive. The observed probability density function of propagation direction of NIWs is consistent with the predictions from the wave capture theory. Submesoscale O(<10 km) motions and their interactions with NIWs are studied theoretically and numerically using high-resolution numerical simulations. Submesoscale fronts (SMFs) with energetic vertical motions in the ocean interior are found to be closely associated with the NIWs. A dynamic mechanism for the SMF development in the presence of background NIWs is proposed. It shows that in convergence (downwelling) regions of NIWs, energy flux of the submesoscale motions converges and the energy is transferred from the NIWs to submesoscale motions, leading to enhanced submesoscale vertical velocity. The opposite is true in divergence (upwelling) zones of NIWs. The underlying dynamics can be understood in terms of wave action conservation of submesoscale motions in the presence of background NIWs. Advisors/Committee Members: Chang, Ping (advisor), Wu, Lixin (advisor), Saravanan, Ramalingam (committee member), DiMarco, Steven (committee member).

Subjects/Keywords: near-inertial internal waves; mesoscale eddies; submesoscale flow

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APA (6^th Edition):

Jing, Z. (2016). A Study of Interactions Between Near-inertial Internal Waves and Mesoscale-to-Submesoscale Flows. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156997

Chicago Manual of Style (16^th Edition):

Jing, Zhao. “A Study of Interactions Between Near-inertial Internal Waves and Mesoscale-to-Submesoscale Flows.” 2016. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/156997.

MLA Handbook (7^th Edition):

Jing, Zhao. “A Study of Interactions Between Near-inertial Internal Waves and Mesoscale-to-Submesoscale Flows.” 2016. Web. 16 Jan 2021.

Vancouver:

Jing Z. A Study of Interactions Between Near-inertial Internal Waves and Mesoscale-to-Submesoscale Flows. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/156997.

Council of Science Editors:

Jing Z. A Study of Interactions Between Near-inertial Internal Waves and Mesoscale-to-Submesoscale Flows. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/156997

Texas A&M University

3. Lee, Kanghyun. The Relationship Between Urban Sprawl and Disaster Resilience: An Exploratory Study.

Degree: Master of Urban Planning, Urban and Regional Sciences, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/157857

► In the wake of ever increasing numbers of natural disasters around the world, further exacerbated by climate change and our growing alarm and vulnerability to… (more)

Subjects/Keywords: urban sprawl; disaster resilience

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APA (6^th Edition):

Lee, K. (2016). The Relationship Between Urban Sprawl and Disaster Resilience: An Exploratory Study. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/157857

Chicago Manual of Style (16^th Edition):

Lee, Kanghyun. “The Relationship Between Urban Sprawl and Disaster Resilience: An Exploratory Study.” 2016. Masters Thesis, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/157857.

MLA Handbook (7^th Edition):

Lee, Kanghyun. “The Relationship Between Urban Sprawl and Disaster Resilience: An Exploratory Study.” 2016. Web. 16 Jan 2021.

Vancouver:

Lee K. The Relationship Between Urban Sprawl and Disaster Resilience: An Exploratory Study. [Internet] [Masters thesis]. Texas A&M University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/157857.

Council of Science Editors:

Lee K. The Relationship Between Urban Sprawl and Disaster Resilience: An Exploratory Study. [Masters Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/157857

Texas A&M University

4. Zamora, Ryan Alexander. Tropical Cyclones in Paleoclimate Simulation.

Degree: PhD, Atmospheric Sciences, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/158978

► This research examines tropical cyclones in simulations of climates very different from modern. The tropical cyclones are simulated via two techniques: explicitly tracking TC-like structures… (more)

▼ This research examines tropical cyclones in simulations of climates very different from modern. The tropical cyclones are simulated via two techniques: explicitly tracking TC-like structures in global climate model output, and by downscaling model output to be used in higher resolution models able to resolve tropical cyclones. These techniques are applied to climates such as the Last Glacial Maximum, mid-Holocene, and in a suite of simulations that feature very hot surface temperatures forced by higher global concentrations of CO2. The simulated tropical cyclone climatologies are compared with the large-scale environmental factors within these climates, in an effort to extend the knowledge of the tropical cyclone response across varying climate conditions. Explicitly resolved storms within CCSM4 did not relate well to a common set of environmental factors across 20th century and LGM climates, and in addition showed that changes in climate are potentially sensitive to the inclusion of the weakest systems, which are controlled by the choice of threshold detection criteria. Sensitivity tests conducted on these storms showed that altering the surface wind speed threshold an initial disturbance must achieve by as little as 20% significantly alters the overall result (showing a greater number of 20th century or Last Glacial Maximum storms generated depending on this choice). We show that the storms generated via Emanuel’s downscaled storms technique relates well in each of the climates to a combination of environmental factors important for TC genesis and development, such as genesis potential and ventilation indices. Regional and temporal changes in these large-scale factors well predict changes in tropical cyclone activity between the different climates. In addition, these storms show relationships in intensity and genesis with warming, particularly with the strongest storms generated. Advisors/Committee Members: Korty, Robert L (advisor), Schumacher, Courtney (committee member), Saravanan, Ramalingam (committee member), Chang, Ping (committee member).

Subjects/Keywords: tropical cyclones; climate change; Paleoclimates

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APA (6^th Edition):

Zamora, R. A. (2016). Tropical Cyclones in Paleoclimate Simulation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158978

Chicago Manual of Style (16^th Edition):

Zamora, Ryan Alexander. “Tropical Cyclones in Paleoclimate Simulation.” 2016. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/158978.

MLA Handbook (7^th Edition):

Zamora, Ryan Alexander. “Tropical Cyclones in Paleoclimate Simulation.” 2016. Web. 16 Jan 2021.

Vancouver:

Zamora RA. Tropical Cyclones in Paleoclimate Simulation. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/158978.

Council of Science Editors:

Zamora RA. Tropical Cyclones in Paleoclimate Simulation. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/158978

Texas A&M University

5. Li, Furong. Statistical Inference for Large Spatial Data.

Degree: PhD, Statistics, 2017, Texas A&M University

URL: http://hdl.handle.net/1969.1/174900

► The availability of large spatial and spatial-temporal data geocoded at accurate locations has fueled increasing interest in spatial modeling and analysis. In this dissertation, we… (more)

▼ The availability of large spatial and spatial-temporal data geocoded at accurate locations has fueled increasing interest in spatial modeling and analysis. In this dissertation, we present one study concerning the inference on properties of a single spatial process, and then turn to multiple processes and provide two modeling approaches exploring the spatially varying relationship between covariates and the response variable of interest. In the first study, we investigate the inference tool based on quasi-likelihood, composite likelihood (CL) method and propose a new weighting scheme to construct a CL for the inference of spatial Gaussian process models. This weight function approximates the optimal weight derived from the theory of estimating equations. It combines block-diagonal approximation and tapering strategy to facilitate computations. Gains in statistical and computational efficiency over existing CL methods are illustrated through simulation studies. The second investigation is the development of a new spatial modeling framework to capture the spatial structure, especially clustered structure in the relationship between response variable and explanatory variables. The proposed method, called Spatially Clustered Coefficient(SCC) regression, results in estimators of varying coefficients, which conveys important information about the changing pattern of the relationship. The SCC method works very effectively in estimation for data either with clustered coefficients or smoothly-varying coefficients, based on our simulation results. Thus, it allows the researchers to explore the spatial structure in the regression coefficient without any priori information. We also derive some oracle inequalities, which provides non-asymptotic error bounds on estimators and predictors. An application of the SCC method to temperature and salinity data in the Atlantic basin is provided for illustration. Motivated by the studies in Geoscience that the influence of turbulent heat flux on sea surface temperature (SST) varies at different spatial scales, we develop a statistical model to quantify the continuous dependence of SST-turbulent heat flux relationship (T-Q relationship) on spatial scales. In particular, we propose a penalized regression model in the spectral domain to estimate the changing relationship with spatial scales. While application to T-Q relationship is the main motivation for this work, it should be emphasized that the penalized spectral regression framework is general and thus is applicable to other phenomena of interest as well. Advisors/Committee Members: Sang, Huiyan (advisor), Longnecker, Michael (committee member), Mallick, Bani (committee member), Saravanan, Ramalingam (committee member).

Subjects/Keywords: Weighted composite likelihood; Spatially clustered coefficient regression; Penalized spectral regression.

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APA (6^th Edition):

Li, F. (2017). Statistical Inference for Large Spatial Data. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174900

Chicago Manual of Style (16^th Edition):

Li, Furong. “Statistical Inference for Large Spatial Data.” 2017. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/174900.

MLA Handbook (7^th Edition):

Li, Furong. “Statistical Inference for Large Spatial Data.” 2017. Web. 16 Jan 2021.

Vancouver:

Li F. Statistical Inference for Large Spatial Data. [Internet] [Doctoral dissertation]. Texas A&M University; 2017. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/174900.

Council of Science Editors:

Li F. Statistical Inference for Large Spatial Data. [Doctoral Dissertation]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/174900

Texas A&M University

6. Hsu, Chuan-Yuan. Wind-Driven Near-Inertial Waves and Their Impact in the Gulf of Mexico.

Degree: PhD, Oceanography, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/173605

► The continental shelf in the Northern Gulf of Mexico is located along the critical latitude (30° N) where local Coriolis frequency is equal to diurnal… (more)

▼ The continental shelf in the Northern Gulf of Mexico is located along the critical latitude (30° N) where local Coriolis frequency is equal to diurnal frequency, and where existence of near-inertial resonance by land-sea breeze (LSB) circulation has been observed. The enhanced near-inertial waves (NIWs) have been argued to energize vertical mixing in the water column of the Northern Gulf. This study first attempts to investigate the impact of wind-driven near-inertial ocean response using both a simple slab ocean model and a high-resolution primitive-equation ocean model forced by different atmospheric wind products. The results show that the near-inertial wind work during boreal summer is closely linked to the structure of land-sea breeze and varies significantly among different wind products, which further affect vertical mixing in the water column. In addition, since the diurnal winds in all of the reanalyzed wind products are weaker than the in situ buoy-observed winds, and there is a clear linear relationship between near-inertial wind strength and near-inertial wind power input, as well as near-inertial surface current kinetic energy, it suggests that NIW activity is likely to be underestimated in the Northern Gulf when these reanalysis winds are used as atmospheric forcing for an ocean model. The second part of this study proposes a new modeling approach to quantify the impact of near-inertial motions on vertical mixing in the Northern Gulf of Mexico during summer and winter season using a full three-dimensional primitive equation model. In this new approach, we introduce a novel filtering technique that simply changes the rotation direction of the clockwise rotating winds within the near-inertial band at every grid point. Since the clockwise rotating near-inertial winds are primarily responsible for near-inertial wave generation in the ocean, this filtering technique effectively suppresses near-inertial waves while keeping total wind variance approximately intact. Comparing to the previous filtering methods that are based on temporal filtering of near-inertial winds, and thus are not variance preserving, the new technique isolates more effectively the impact of near-inertial waves on ocean mixing. Advisors/Committee Members: Chang, Ping (advisor), Howard, Matthew (advisor), Saravanan, Ramalingam (committee member), Hetland, Robert (committee member).

Subjects/Keywords: near-inertial waves; Gulf of Mexico

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APA (6^th Edition):

Hsu, C. (2018). Wind-Driven Near-Inertial Waves and Their Impact in the Gulf of Mexico. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/173605

Chicago Manual of Style (16^th Edition):

Hsu, Chuan-Yuan. “Wind-Driven Near-Inertial Waves and Their Impact in the Gulf of Mexico.” 2018. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/173605.

MLA Handbook (7^th Edition):

Hsu, Chuan-Yuan. “Wind-Driven Near-Inertial Waves and Their Impact in the Gulf of Mexico.” 2018. Web. 16 Jan 2021.

Vancouver:

Hsu C. Wind-Driven Near-Inertial Waves and Their Impact in the Gulf of Mexico. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/173605.

Council of Science Editors:

Hsu C. Wind-Driven Near-Inertial Waves and Their Impact in the Gulf of Mexico. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/173605

Texas A&M University

7. Steinweg-Woods, Jesse Matthew. A Lagrangian Analysis of Midlatitude Air-Sea Interaction Associated with Mesoscale Oceanic Eddies.

Degree: PhD, Atmospheric Sciences, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/157015

► Oceanic eddies, approximately 80 km in diameter in the mid-latitude Atlantic Ocean, are frequently generated along the Gulf Stream. These eddies contain a sea surface… (more)

▼ Oceanic eddies, approximately 80 km in diameter in the mid-latitude Atlantic Ocean, are frequently generated along the Gulf Stream. These eddies contain a sea surface temperature anomaly as they spin and break away from the main current. Oceanic eddies have been shown to effect the lower atmosphere in several regions in prior studies, influencing rainfall rates, cloud cover, and surface wind speeds in satellite observations. Eddy features are located using an automated detection algorithm and the atmosphere surrounding each eddy's location is studied. Coupled global and regional models, utilizing both atmospheric and oceanic components, are tested to investigate their capability of demonstrating the atmospheric response compared to observations. It is found that the atmospheric influence of oceanic eddies is primarily limited to the boundary layer, with an exception for vertical motion influence that can extend beyond it. Eddies with a positive sea surface temperature anomaly core increase the formation of low-level clouds and rainfall slightly downstream of the eddy center, with clouds forming consistently at a height of approximately 850 hPa in models and reanalysis data. The vertical mixing mechanism is shown to be the cause of the wind response to oceanic eddy influence. This is based on a dipolar pattern of wind divergence aligning with the sea surface temperature gradient, along with a change in horizontal wind speed close to the top of the boundary layer due to vertical momentum transfer. The results show coupled models overestimate the coupling strength between sea surface temperatures and the atmospheric response compared to observations. This indicates coupled models are capable of adequately simulating the atmospheric response, as long as the oceanic component's resolution is eddy resolving. In the regional model, parameterized convection showed a very similar result to explicitly resolving the convection. Therefore, the atmospheric response to oceanic eddies can be simulated properly even if the convection has been parameterized. Advisors/Committee Members: Saravanan, Ramalingam (advisor), Chang, Ping (committee member), Nielsen-Gammon, John (committee member), Quiring, Steven (committee member).

Subjects/Keywords: oceanic eddies; atmospheric response; air-sea interaction; high-resolution modeling

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APA (6^th Edition):

Steinweg-Woods, J. M. (2016). A Lagrangian Analysis of Midlatitude Air-Sea Interaction Associated with Mesoscale Oceanic Eddies. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/157015

Chicago Manual of Style (16^th Edition):

Steinweg-Woods, Jesse Matthew. “A Lagrangian Analysis of Midlatitude Air-Sea Interaction Associated with Mesoscale Oceanic Eddies.” 2016. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/157015.

MLA Handbook (7^th Edition):

Steinweg-Woods, Jesse Matthew. “A Lagrangian Analysis of Midlatitude Air-Sea Interaction Associated with Mesoscale Oceanic Eddies.” 2016. Web. 16 Jan 2021.

Vancouver:

Steinweg-Woods JM. A Lagrangian Analysis of Midlatitude Air-Sea Interaction Associated with Mesoscale Oceanic Eddies. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/157015.

Council of Science Editors:

Steinweg-Woods JM. A Lagrangian Analysis of Midlatitude Air-Sea Interaction Associated with Mesoscale Oceanic Eddies. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/157015

Texas A&M University

8. Sansom, Taylor Lee. Spatial Correlations in General Circulation Models and Observation Reanalysis.

Degree: MS, Atmospheric Sciences, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/153216

► The purpose of this study was to research the geographical structure and time evolution of spatial correlations of general circulation models, energy balance models, observations… (more)

Subjects/Keywords: climate statistics; spatial correlation; correlation function; second moment statistics

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APA (6^th Edition):

Sansom, T. L. (2014). Spatial Correlations in General Circulation Models and Observation Reanalysis. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153216

Chicago Manual of Style (16^th Edition):

Sansom, Taylor Lee. “Spatial Correlations in General Circulation Models and Observation Reanalysis.” 2014. Masters Thesis, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/153216.

MLA Handbook (7^th Edition):

Sansom, Taylor Lee. “Spatial Correlations in General Circulation Models and Observation Reanalysis.” 2014. Web. 16 Jan 2021.

Vancouver:

Sansom TL. Spatial Correlations in General Circulation Models and Observation Reanalysis. [Internet] [Masters thesis]. Texas A&M University; 2014. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/153216.

Council of Science Editors:

Sansom TL. Spatial Correlations in General Circulation Models and Observation Reanalysis. [Masters Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153216

Texas A&M University

9. Lin, Fang-Yu. Combining Strategies for Parallel Stochastic Approximation Monte Carlo Algorithm of Big Data.

Degree: PhD, Statistics, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/153814

► Modeling and mining with massive volumes of data have become popular in recent decades. However, it is difficult to analyze on a single commodity computer… (more)

▼ Modeling and mining with massive volumes of data have become popular in recent decades. However, it is difficult to analyze on a single commodity computer because the size of data is too large. Parallel computing is widely used. As a natural methodology, the divide-and-combine (D&C) method has been applied in parallel computing. The general method of D&C is to use MCMC algorithm in each divided data set. However, MCMC algorith is computationally expensive because it requires a large number of iterations and is prone to get trapped into local optima. On the other hand, Stochastic Approximation in Monte Carlo algorithm (SAMC), a very sophisticated algorithm in theory and applications, can avoid getting trapped into local optima and produce more accurate estimation than the conventional MCMC algorithm does. Motivated by the success of SAMC, we propose parallel SAMC algorithm that can be utilized on massive data and is workable in parallel computing. It can also be applied for model selection and optimization problem. The main challenge of the parallel SAMC algorithm is how to combine the results from each parallel subset. In this work, three strategies to overcome the combining difficulties are proposed. From the simulation results, these strategies result in significant time saving and accurate estimation. Synthetic Aperture Radar Interferometry (InSAR) is a technique of analyzing deformation caused by geophysical processes. However, it is limited by signal losses which are from topographic residuals. In order to analyze the surface deformation, we have to distinguish signal losses. Many methods assume the noise has second order stationary structure without testing it. The objective of this study is to examine the second order stationary assumption for InSAR noise and develop a parametric nonstationary model in order to demonstrate the effect of making incorrect assumption on random field. It indicates that wrong stationary assumption will result in bias estimation and large variation. Advisors/Committee Members: Liang, Faming (advisor), Carroll, Raymond (advisor), Longnecker, Michael (committee member), Saravanan, Ramalingam (committee member).

Subjects/Keywords: Stochastic Approximation Monte Carlo; Parallel Computation; MCMC; Big Data

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APA (6^th Edition):

Lin, F. (2014). Combining Strategies for Parallel Stochastic Approximation Monte Carlo Algorithm of Big Data. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153814

Chicago Manual of Style (16^th Edition):

Lin, Fang-Yu. “Combining Strategies for Parallel Stochastic Approximation Monte Carlo Algorithm of Big Data.” 2014. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/153814.

MLA Handbook (7^th Edition):

Lin, Fang-Yu. “Combining Strategies for Parallel Stochastic Approximation Monte Carlo Algorithm of Big Data.” 2014. Web. 16 Jan 2021.

Vancouver:

Lin F. Combining Strategies for Parallel Stochastic Approximation Monte Carlo Algorithm of Big Data. [Internet] [Doctoral dissertation]. Texas A&M University; 2014. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/153814.

Council of Science Editors:

Lin F. Combining Strategies for Parallel Stochastic Approximation Monte Carlo Algorithm of Big Data. [Doctoral Dissertation]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153814

Texas A&M University

10. Han, Fan. A Morphing-based Approach for the Verification of Precipitation Forecasts.

Degree: MS, Atmospheric Sciences, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/154042

► This thesis described a morphing-based precipitation verification strategy inspired by Keil and Craig. This strategy is based on an optical flow algorithm to morph the… (more)

Subjects/Keywords: Precipitation verification; morphing

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APA (6^th Edition):

Han, F. (2014). A Morphing-based Approach for the Verification of Precipitation Forecasts. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/154042

Chicago Manual of Style (16^th Edition):

Han, Fan. “A Morphing-based Approach for the Verification of Precipitation Forecasts.” 2014. Masters Thesis, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/154042.

MLA Handbook (7^th Edition):

Han, Fan. “A Morphing-based Approach for the Verification of Precipitation Forecasts.” 2014. Web. 16 Jan 2021.

Vancouver:

Han F. A Morphing-based Approach for the Verification of Precipitation Forecasts. [Internet] [Masters thesis]. Texas A&M University; 2014. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/154042.

Council of Science Editors:

Han F. A Morphing-based Approach for the Verification of Precipitation Forecasts. [Masters Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/154042

Texas A&M University

11. Coy Jr., James Joseph. Evaluating the Benefits of Using Longwave Infrared and Millimeter/Sub-millimeter Bands to Explore Ice Cloud Characteristics Through Polarized Vector Radiative Transfer Simulations.

Degree: MS, Atmospheric Sciences, 2019, Texas A&M University

URL: http://hdl.handle.net/1969.1/186936

► A comprehensive study on evaluating the usefulness of relatively high frequency millimeter/sub-millimeter (mm/sub-mm) bands (greater than 150 GHz) and longwave infrared (LWIR) atmospheric window bands… (more)

▼ A comprehensive study on evaluating the usefulness of relatively high frequency millimeter/sub-millimeter (mm/sub-mm) bands (greater than 150 GHz) and longwave infrared (LWIR) atmospheric window bands to infer ice cloud properties will be conducted for this thesis. A sizable amount of mm/sub-mm bands have been considered from radiometric and polarimetric studies to be useful for observing ice clouds with lower mm/sub-mm wavelengths (higher frequencies) being able to observe even optically thin cirrus. The LWIR atmospheric window has been thoroughly investigated for their feasibility to also observe ice clouds, especially optically thin cirrus. However, there have not been many studies conducted using several of these relatively high frequency bands or polarimetric LWIR observations to infer ice cloud properties. There have also not been many studies using simulated ice clouds composed of the latest ice particle habit mixtures and single-scattering properties. The single-scattering property databases have considered dependencies such as surface roughness and ambient temperature. This thesis will be focusing on performing simulations on ice clouds using the wavelengths of 440.87 μm (680 GHz), 707.06 um (424 GHz), 922.44 um (325 GHz), 1362.69 um (220 GHz), and 1638.21 um (183 GHz) for the mm/sub-mm regime and 8.6 um, 10.6 um, and 12 um wavelengths of the IR regime. The Atmospheric Radiative Transfer Model (ARTS) will be used to conduct the simulations for 1D atmospheres corresponding to the tropical region. The ice cloud simulations were performed for combinations of ice water path (IWP) and effective diameter (Dvevfvf). IWP and Dvevfvf look-up tables (LUT) were created in order to evaluate the feasibility of retrieving these values. These LUTs were then used to retrieve IWP and Dvevfvf for the 1D vertically heterogeneous ice cloud scenarios which will be using 3D ice clouds produced by Cloudgen – a stochastic cloud generator. The brightness temperature (Tvb) parameters that were used to infer the cloud properties are the split-window technique (BTD), brightness temperature depression relative to clear-sky (Tvb), and the polarization difference (PD). Advisors/Committee Members: Yang, Ping (advisor), Saravanan, Ramalingam (advisor), Bowman, Kenneth (committee member), Filippi, Anthony (committee member).

Subjects/Keywords: Ice Clouds; Radiative Transfer; Radiative Transfer Simulation; Infrared Wavelengths; Microwave (mm/sub-mm) Wavelengths; Polarization; Ice Water Path; Effective Diameter; Retrievals

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APA (6^th Edition):

Coy Jr., J. J. (2019). Evaluating the Benefits of Using Longwave Infrared and Millimeter/Sub-millimeter Bands to Explore Ice Cloud Characteristics Through Polarized Vector Radiative Transfer Simulations. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/186936

Chicago Manual of Style (16^th Edition):

Coy Jr., James Joseph. “Evaluating the Benefits of Using Longwave Infrared and Millimeter/Sub-millimeter Bands to Explore Ice Cloud Characteristics Through Polarized Vector Radiative Transfer Simulations.” 2019. Masters Thesis, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/186936.

MLA Handbook (7^th Edition):

Coy Jr., James Joseph. “Evaluating the Benefits of Using Longwave Infrared and Millimeter/Sub-millimeter Bands to Explore Ice Cloud Characteristics Through Polarized Vector Radiative Transfer Simulations.” 2019. Web. 16 Jan 2021.

Vancouver:

Coy Jr. JJ. Evaluating the Benefits of Using Longwave Infrared and Millimeter/Sub-millimeter Bands to Explore Ice Cloud Characteristics Through Polarized Vector Radiative Transfer Simulations. [Internet] [Masters thesis]. Texas A&M University; 2019. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/186936.

Council of Science Editors:

Coy Jr. JJ. Evaluating the Benefits of Using Longwave Infrared and Millimeter/Sub-millimeter Bands to Explore Ice Cloud Characteristics Through Polarized Vector Radiative Transfer Simulations. [Masters Thesis]. Texas A&M University; 2019. Available from: http://hdl.handle.net/1969.1/186936

Texas A&M University

12. Vogel, Jonathan 1988-. Simulation of Aerosol-Cloud Interactions in the WRF Model at the Southern Great Plains Site.

Degree: MS, Atmospheric Sciences, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/148070

► The aerosol direct and indirect effects were investigated for three specific cases during the March 2000 Cloud IOP at the SGP site by using a… (more)

▼ The aerosol direct and indirect effects were investigated for three specific cases during the March 2000 Cloud IOP at the SGP site by using a modified WRF model. The WRF model was previously altered to include a two-moment bulk microphysical scheme for the aerosol indirect effect and a modified Goddard shortwave radiation scheme for the aerosol direct effect. The three cases studied include a developing low pressure system, a low precipitation event of mainly cirrus clouds, and a cold frontal passage. Three different aerosol profiles were used with surface concentrations ranging from 210 cm-3 to 12,000 cm-3. In addition, each case and each aerosol profile was run both with and without the aerosol direct effect. Regardless of the case, increasing the aerosol concentration generally increased cloud water and droplet values while decreasing rain water and droplet values. Increased aerosols also decreased the surface shortwave radiative flux for every case; which was greatest when the aerosol direct effect was included. For convective periods during polluted model runs, the aerosol direct effect lowered the surface temperature and reduced convection leading to a lower cloud fraction. During most convective periods, the changes to cloud, rain, and ice water mixing ratios and number concentrations produced a nonlinear precipitation trend. A balance between these values was achieved for moderate aerosol profiles, which produced the highest convective precipitation rates. In non-convective cases, due to the presence of ice particles, aerosol concentration and precipitation amounts were positively correlated. The aerosol threshold between precipitation enhancement and suppression should be further studied for specific cloud types as well as for specific synoptic weather patterns to determine its precise values. Advisors/Committee Members: Zhang, Renyi (advisor), Saravanan, Ramalingam (committee member), Schumacher, Courtney (committee member), Ying, Qi (committee member).

Subjects/Keywords: aerosol indirect effect; aerosol direct effect; cloud modeling; aerosol-cloud interactions; atmospheric aerosols

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APA (6^th Edition):

Vogel, J. 1. (2012). Simulation of Aerosol-Cloud Interactions in the WRF Model at the Southern Great Plains Site. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/148070

Chicago Manual of Style (16^th Edition):

Vogel, Jonathan 1988-. “Simulation of Aerosol-Cloud Interactions in the WRF Model at the Southern Great Plains Site.” 2012. Masters Thesis, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/148070.

MLA Handbook (7^th Edition):

Vogel, Jonathan 1988-. “Simulation of Aerosol-Cloud Interactions in the WRF Model at the Southern Great Plains Site.” 2012. Web. 16 Jan 2021.

Vancouver:

Vogel J1. Simulation of Aerosol-Cloud Interactions in the WRF Model at the Southern Great Plains Site. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/148070.

Council of Science Editors:

Vogel J1. Simulation of Aerosol-Cloud Interactions in the WRF Model at the Southern Great Plains Site. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/148070

Texas A&M University

13. Kim, Who Myung. Understanding the Long-Term Change of the Atlantic Meridional Overturning Circulation (AMOC) during the Late Twentieth Century.

Degree: PhD, Oceanography, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/149596

► The strength of the Atlantic meridional overturning circulation (AMOC) is believed to be associated with changes in surface buoyancy in the subpolar North Atlantic, which… (more)

▼ The strength of the Atlantic meridional overturning circulation (AMOC) is believed to be associated with changes in surface buoyancy in the subpolar North Atlantic, which naturally leads to a notion that the AMOC has been weakening under global warming. Yet, a variety source of observations and its assimilation into ocean circulation models have not supported such an AMOC decline so far. In this study, an aspect that has not been paid attention, regarding the maintenance of the AMOC strength, is explored: storm activity in the subpolar North Atlantic (NA). An analysis using reanalysis data shows that the wintertime turbulent heat flux variability in the LS deep convection region is largely controlled by a small number of extreme heat flux event days, suggesting a pivotal role of winter storms in prompting LS deep-water formation. A set of forced ocean-ice model simulations, in which synoptic winter storm activity associated with these event days is either suppressed or doubled over the subpolar NA, confirms the above analysis as the altered storm activity results in a substantial change in LS convection and the AMOC strength. These experiments also show an upward AMOC trend during the late twentieth century, the degree of which is to some extent related to the intensity of storm activity in the LS. The upward AMOC trend found in the first part of the dissertation opposes to a downward AMOC trend in the twentieth century coupled model simulations employing the identical ocean component. An analysis suggests that contrast to the ocean-ice model, storm activity in the LS convection region and associated heat flux decreases during the late twentieth century. Although there is also a buoyancy increase over the LS, the wintertime heat flux decrease appears to be a more dominant factor for a decrease in convection in the LS, as an increasing freshwater input from Arctic/Subarctic Ocean bypasses the interior LS along the western boundary current. Therefore, the downward AMOC trend in the coupled model can be linked ultimately to the decreasing storm activity over the LS. This study therefore suggests that storm activity over the major convection regions needs to be paid further attention in assessing AMOC variations, including long-term trend in response to a warming scenario, in future studies. Advisors/Committee Members: Chang, Ping (advisor), Stoessel, Achim (advisor), Saravanan, Ramalingam (committee member), Orsi, Alejandro (committee member).

Subjects/Keywords: Atlantic Meridional Overturning Circulation; AMOC; AMOC trend; AMOC variability; North Atlantic storm track; extratropical storms; oceanic deep convection; deep convection; Labrador Sea; POP2; CCSM4; CMIP5

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APA (6^th Edition):

Kim, W. M. (2013). Understanding the Long-Term Change of the Atlantic Meridional Overturning Circulation (AMOC) during the Late Twentieth Century. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/149596

Chicago Manual of Style (16^th Edition):

Kim, Who Myung. “Understanding the Long-Term Change of the Atlantic Meridional Overturning Circulation (AMOC) during the Late Twentieth Century.” 2013. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/149596.

MLA Handbook (7^th Edition):

Kim, Who Myung. “Understanding the Long-Term Change of the Atlantic Meridional Overturning Circulation (AMOC) during the Late Twentieth Century.” 2013. Web. 16 Jan 2021.

Vancouver:

Kim WM. Understanding the Long-Term Change of the Atlantic Meridional Overturning Circulation (AMOC) during the Late Twentieth Century. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/149596.

Council of Science Editors:

Kim WM. Understanding the Long-Term Change of the Atlantic Meridional Overturning Circulation (AMOC) during the Late Twentieth Century. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/149596

Texas A&M University

14. Zhu, Xiaojie. Influence of Mean State on Climate Variability at Interannual and Decadal Time Scales.

Degree: PhD, Atmospheric Sciences, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/150993

► This dissertation reports on studies on the role of the mean state in modulating climate variability at interannual and decadal time scales. In the atmosphere,… (more)

▼ This dissertation reports on studies on the role of the mean state in modulating climate variability at interannual and decadal time scales. In the atmosphere, the nonlinear superposition of mean flow and anomalous flow has important implications for many phenomena associated with variables that are nonlinear by definition, such as the vertical wind shear and surface wind speed. In the first part of this dissertation, the influence of mean flow and anomalous flow on vertical wind shear variability is studied in observations and numerical model simulations. At interannual timescales, the ENSO-shear relationship is compared between observations and numerical model simulations. It is shown that there is strong influence of mean flow on the ENSO-shear relationship. For same anomalous flow, different mean flows could give rise to a different ENSO-shear relationship. The nonlinear superposition of mean flow and anomalous flow also helps explains the dipole mode of tropical Atlantic vertical wind shear variability seen in observations and models, which implies opposite variation of vertical wind shear over the two sides of the tropical Atlantic. This has important implications for predicting phenomena such as Atlantic hurricanes, whose variations are modulated by vertical shear variability. The dissertation also addresses the role of the mean surface wind in decadal variability and predictability, as manifested through the Wind-Evaporation-SST (WES) feedback. The nonlinear superposition of anomalous surface wind on the mean trade wind can give rise to a positive WES feedback, which can amplify tropical climate variability. To study this feedback, we carried out ensembles of decadal climate predictions using the CAM3 atmospheric model coupled to a slab ocean model (CAM3- SOM) with prescribed ocean transport and simple extrapolative prescriptions of future external forcings. Mechansitic sensitivity runs using the CAM3-SOM were also carried out, where the WES feedback was switched off by prescribing climatological surface wind. Results suggest that switching off the WES feedback enhances the prediction skill over some regions, especially over the eastern tropical Pacific, by increasing the signal- to-noise ratio. To address the issue of cold bias noted in the decadal prediction experiments, we carried out additional sensitivity experiments where we used an adaptive formulation for the prescribed oceanic heat transport (Q-flux) in the slab ocean. The results from these experiments demonstrate that the mean oceanic heat transport plays a crucial role in influencing decadal predictability, by helping improve predictions of the trend component of decadal variations. Advisors/Committee Members: Saravanan, Ramalingam (advisor), Chang, Ping (committee member), North, Gerald R (committee member), Schumacher, Courtney (committee member).

Subjects/Keywords: climate variability; wind-evaporation-sst feedback; decadal predictability; vertical wind shear

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

APA (6^th Edition):

Zhu, X. (2013). Influence of Mean State on Climate Variability at Interannual and Decadal Time Scales. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/150993

Chicago Manual of Style (16^th Edition):

Zhu, Xiaojie. “Influence of Mean State on Climate Variability at Interannual and Decadal Time Scales.” 2013. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/150993.

MLA Handbook (7^th Edition):

Zhu, Xiaojie. “Influence of Mean State on Climate Variability at Interannual and Decadal Time Scales.” 2013. Web. 16 Jan 2021.

Vancouver:

Zhu X. Influence of Mean State on Climate Variability at Interannual and Decadal Time Scales. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/150993.

Council of Science Editors:

Zhu X. Influence of Mean State on Climate Variability at Interannual and Decadal Time Scales. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/150993

Texas A&M University

15. Liu, Xue. Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics.

Degree: PhD, Oceanography, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/173883

► As resolution of observations and climate models continues to improve, it has become increasingly evident that mesoscale eddies – a ubiquitous feature of the world… (more)

▼ As resolution of observations and climate models continues to improve, it has become increasingly evident that mesoscale eddies – a ubiquitous feature of the world ocean – can interact with the overlying atmosphere, potentially affecting large-scale atmospheric and oceanic circulation and climate. Improving our understanding of this ocean mesoscale eddy – atmosphere (OME-A) interaction has important implications for improving climate simulations and predictions. This dissertation contributes to this understanding by focusing on two elements of OME-A interaction. The first element deals with the influence of ocean mesoscale eddies on rainfall. By comparing three different satellite-derived rainfall datasets, we examined the robustness of the rainfall response to ocean eddy induced mesoscale sea-surface temperature anomalies (SSTAs). The three datasets are the Tropical Rainfall Measurement Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA), NOAA Climate Prediction Center (CPC) Morphing Technique (CMORPH) global precipitation and newly available Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) that is based on the latest remote sensing technology with finer spatial and temporal resolution. The results show that 1) all datasets exhibit a similar rainfall response to ocean eddies, but the amplitude of the rainfall response varies among datasets with IMERG producing the strongest and most coherent rainfall response, despite the weakest time-mean rainfall, 2) eddy-induced precipitation response is significantly stronger in winter than in summer and over warm eddies than cold eddies, and these asymmetries in rainfall response is more robust in IMERG than in the other two datasets. Documenting and analyzing these asymmetric rainfall responses are important for understanding the potential role of ocean eddies in forcing the large-scale atmospheric circulation and climate. The second element examines the effect of OME-A interaction on ocean eddy wind power that plays a vital role in dissipating eddy kinetic energy (EKE). By using a scaling analysis and analyzing eddy-resolving coupled climate model simulations, we not only quantify the impact of OME-A interaction on eddy wind power, but also provide a mechanistic understanding of the underlying process. Results show that the impact of OME-A feedback on eddy wind power, albeit smaller than that due to ocean current feedback, is significant and amounts to about 30-40% reduction of the value without OME-A interaction. Therefore, in the absence of OME-A interaction, eddy wind power is significantly overestimated, thus providing a too-strong sink for EKE. Advisors/Committee Members: Chang, Ping (advisor), Lin, Xiaopei (advisor), Saravanan, Ramalingam (committee member), Szunyogh, Istvan (committee member).

Subjects/Keywords: Oceanic Mesoscale Eddies; Air-Sea Interaction; Rainfall; Wind Power

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APA (6^th Edition):

Liu, X. (2018). Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/173883

Chicago Manual of Style (16^th Edition):

Liu, Xue. “Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics.” 2018. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/173883.

MLA Handbook (7^th Edition):

Liu, Xue. “Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics.” 2018. Web. 16 Jan 2021.

Vancouver:

Liu X. Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/173883.

Council of Science Editors:

Liu X. Elements of Ocean Mesoscale Eddy-Atmosphere Interactions in Extratropics. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/173883

Texas A&M University

16. Jeong, Jaehong. Spatial-Temporal Models for Processes on the Sphere and their Application in Climate Problem.

Degree: PhD, Statistics, 2015, Texas A&M University

URL: http://hdl.handle.net/1969.1/155553

► There have been noticeable advancements in developing parametric covariance models for spatial and spatial-temporal data in climate science. However, literature on covariance models for processes… (more)

▼ There have been noticeable advancements in developing parametric covariance models for spatial and spatial-temporal data in climate science. However, literature on covariance models for processes on the surface of a sphere is still sparse, due to its mathematical difficulties. In this dissertation, we study random fields and spatial-temporal covariance functions on the surface of a sphere. At first, smooth climate variables need smooth covariance functions. We develop a methodology to construct parametric covariance functions using the great circle distance for spatial processes, geared towards smooth processes on the surface of a sphere. We integrate a non-differential process over a small neighborhood on the surface of a sphere, which result in a smoother process. The resulting model is isotropic and positive definite on the surface of a sphere with the great circle distance, with a natural extension for nonstationarity case. Extensive numerical comparisons of our model, with a Matérn covariance model using the great circle distance as well as the chordal distance, are presented. Next, utilizing the one-to-one mapping between the Euclidean distance and the great circle distance, isotropic and positive definite functions in a Euclidean space can be used as covariance functions on the surface of a sphere. However, this approach may result in physically unrealistic distortion on the sphere especially for large distances. We consider several classes of covariance functions on the surface of a sphere, defined with either the great circle distance or the Euclidean distance, and investigate their impact upon prediction. We demonstrate that covariance functions originally defined in the Euclidean distance may not be adequate for some global data. Finally, climate variables often vary in both space and time and it has become popular to model multiple processes jointly. We consider the extension of the bivariate Matérn covariance models for spatial-temporal processes on the surface of a sphere. Since data sets have large dimension, a number of challenges arise when performing parameter estimation and prediction. To overcome the computational challenges, we consider the Discrete Fourier Transformation (DFT). We present a method to compute the approximate likelihood efficiently for the case of regularly spaced data of large dimension. Advisors/Committee Members: Jun, Mikyoung (advisor), Subba Rao, Suhasini (committee member), Katzfuss, Matthias (committee member), Saravanan, Ramalingam (committee member).

Subjects/Keywords: Covariance function; Chordal distance; Great circle distance; Process on a sphere

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APA (6^th Edition):

Jeong, J. (2015). Spatial-Temporal Models for Processes on the Sphere and their Application in Climate Problem. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/155553

Chicago Manual of Style (16^th Edition):

Jeong, Jaehong. “Spatial-Temporal Models for Processes on the Sphere and their Application in Climate Problem.” 2015. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/155553.

MLA Handbook (7^th Edition):

Jeong, Jaehong. “Spatial-Temporal Models for Processes on the Sphere and their Application in Climate Problem.” 2015. Web. 16 Jan 2021.

Vancouver:

Jeong J. Spatial-Temporal Models for Processes on the Sphere and their Application in Climate Problem. [Internet] [Doctoral dissertation]. Texas A&M University; 2015. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/155553.

Council of Science Editors:

Jeong J. Spatial-Temporal Models for Processes on the Sphere and their Application in Climate Problem. [Doctoral Dissertation]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/155553

Texas A&M University

17. Wang, Yuan. Aerosol-cloud Interactions from Urban, Regional, to Global Scales.

Degree: PhD, Atmospheric Sciences, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/151115

► The studies in this dissertation aim at advancing our scientific understandings about physical processes involved in the aerosol-cloud-precipitation interaction and quantitatively assessing the impacts of… (more)

▼ The studies in this dissertation aim at advancing our scientific understandings about physical processes involved in the aerosol-cloud-precipitation interaction and quantitatively assessing the impacts of aerosols on the cloud systems with diverse scales over the globe on the basis of the observational data analysis and various modeling studies. Long-term impacts of aerosols on precipitation and lightning over the Pearl River Delta megacity area in China are identified through the analysis of seven-year measurements of precipitation, lightning flashes, and visibility from 2000 to 2006. The cloud resolving - Weather Research and Forecasting (CR-WRF) model with a two- moment bulk microphysical scheme is employed to simulate a mesoscale convective system in the Guangzhou megacity area and to elucidate the effects of aerosols on cloud processes, precipitation, and lightning activity. The responses of hydrometeors and latent heat release to different aerosol loadings reveal the physical mechanism for the precipitation and lightning enhancement in the Guangzhou megacity area, showing more efficient mixed phase processes and intensified convection under the polluted aerosol condition. Sensitivity modeling experiments are performed for maritime warm stratocumulus clouds over the southeast Pacific Ocean to evaluate the microphysical parameterizations for simulations of the aerosol effects in regional and global climate models. The Morrison double-moment bulk microphysical scheme presently implemented in the WRF model is modified by replacing the fixed aerosols in the original bulk scheme with a prognostic double-moment aerosol representation to predict both aerosol number concentration and mass mixing ratio. The impacts of the parameterizations of diffusional growth and autoconversion of cloud droplets and the selection of the embryonic raindrop radius on the performance of the bulk microphysical scheme are also evaluated. The impacts of Asian pollution outflows on the Pacific storm track are assessed utilizing reanalysis data, a hierarchical modeling approach and the multi-scale aerosol- climate modeling frame. Statistical analysis of two sets of reanalysis data suggests a strengthened trend of the storm track intensity over the North Pacific since 1979. The two-month seasonal simulations using a CR-WRF model with a two-moment bulk microphysics are performed to examine the aerosol effects on the Pacific storm track intensity. Subsequently, the anomalies of the diabatic heating rate by the Asian pollution outflow derived from the CR-WRF simulations have been prescribed in the NACR Community Atmosphere Model (CAM5) to provide the aerosol forcing terms. The forced GCM well reproduces an enhancement in the intensity of storm track, compared to the unforced model simulations. Similarly, under the multi-scale aerosol-climate modeling frame, the comparisons of the simulated present day versus pre-industrial climate corresponding to two different aerosol scenarios … Advisors/Committee Members: Zhang, Renyi (advisor), Saravanan, Ramalingam (committee member), Schumacher, Courtney (committee member), Ying, Qi (committee member), Liu, Yangang (committee member).

Subjects/Keywords: aerosol; cloud; climate; modeling

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APA (6^th Edition):

Wang, Y. (2013). Aerosol-cloud Interactions from Urban, Regional, to Global Scales. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151115

Chicago Manual of Style (16^th Edition):

Wang, Yuan. “Aerosol-cloud Interactions from Urban, Regional, to Global Scales.” 2013. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/151115.

MLA Handbook (7^th Edition):

Wang, Yuan. “Aerosol-cloud Interactions from Urban, Regional, to Global Scales.” 2013. Web. 16 Jan 2021.

Vancouver:

Wang Y. Aerosol-cloud Interactions from Urban, Regional, to Global Scales. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/151115.

Council of Science Editors:

Wang Y. Aerosol-cloud Interactions from Urban, Regional, to Global Scales. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151115

Texas A&M University

18. Li, Pin. Quantifying the Contribution of Mean Flow and Eddy Advection to the Warm SST Bias in the Southeast Tropical Atlantic Region.

Degree: PhD, Oceanography, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/174045

► In current-generation climate models, the warm sea surface temperature (SST) bias problem is most commonly seen in the eastern boundary upwelling systems (EBUSs), and is… (more)

▼ In current-generation climate models, the warm sea surface temperature (SST) bias problem is most commonly seen in the eastern boundary upwelling systems (EBUSs), and is most pronounced and most prevalent in the Southeast Tropical Atlantic (SETA) region. Previous studies have shown that the coastal wind pattern in this region, namely the Benguela low-level coastal jet (BLLCJ), is of great importance for the generation of such SST bias, because the coastal ocean circulation is highly sensitive to the off-shore structure of the wind forcing. Using an eddy-resolving regional ocean model, we first show that the SST bias in the region is drastically reduced when forced with simulated winds from a high-resolution regional atmospheric model. We subsequently demonstrate that the SST bias is highly sensitive to the spatial structure of the wind stress curl (WSC). We also find that when the ocean model is forced by a realistic high-resolution wind, the ocean model resolution is of second order importance in reducing the SST bias. Furthermore, we use a double-time average (DTA) method to quantify the contribution of heat budget terms, and show that the horizontal advection contributes significantly to the SST bias. We then examined the question: To what extent do ocean eddies play a role in balancing the coastal ocean heat budget and affecting the SST bias? By experimenting with a submesoscale eddy-permitting regional ocean model, we show that ocean eddies in the Southeast Tropical Atlantic region are most energetic near the Angola-Benguela Front (ABF), the Lüderitz Upwelling Cell region and the Agulhas Leakage region. In these three regions, comparisons between the two model simulations forced with the low- vs high-resolution winds suggest that the SST bias is mainly generated by mean flow advection with ocean eddies playing the role of counteracting the warming induced by the mean flow advection in this region. Advisors/Committee Members: Chang, Ping (advisor), Lin, Xiaopei (committee member), Hetland, Robert (committee member), Stössel, Achim (committee member), Saravanan, Ramalingam (committee member).

Subjects/Keywords: Climate model; SST bias; southeast tropical Atlantic; Benguela low-level coastal jet; Angola Current; Benguela Current; upwelling; eddy advection

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APA (6^th Edition):

Li, P. (2018). Quantifying the Contribution of Mean Flow and Eddy Advection to the Warm SST Bias in the Southeast Tropical Atlantic Region. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174045

Chicago Manual of Style (16^th Edition):

Li, Pin. “Quantifying the Contribution of Mean Flow and Eddy Advection to the Warm SST Bias in the Southeast Tropical Atlantic Region.” 2018. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/174045.

MLA Handbook (7^th Edition):

Li, Pin. “Quantifying the Contribution of Mean Flow and Eddy Advection to the Warm SST Bias in the Southeast Tropical Atlantic Region.” 2018. Web. 16 Jan 2021.

Vancouver:

Li P. Quantifying the Contribution of Mean Flow and Eddy Advection to the Warm SST Bias in the Southeast Tropical Atlantic Region. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/174045.

Council of Science Editors:

Li P. Quantifying the Contribution of Mean Flow and Eddy Advection to the Warm SST Bias in the Southeast Tropical Atlantic Region. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/174045

Texas A&M University

19. Herrera, Michael Aaron. Techniques for the Improvement of Numerical Weather Prediction: Investigating the Dynamics of Forecast Uncertainty and the Implementation of Regionally Enhanced Global Data Assimilation.

Degree: PhD, Atmospheric Sciences, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/159097

► This dissertation describes and shows results from two projects which focused on investigating and improving current methods of numerical weather prediction. First, we show a… (more)

▼ This dissertation describes and shows results from two projects which focused on investigating and improving current methods of numerical weather prediction. First, we show a new data assimilation (DA) approach that produces a global analysis that is enhanced by information from multiple regions of a limited area model (LAM). The enhancement is introduced by blending the model states from the global and regional models and using the blended state to compute the innovations (the difference between the observations and their predicted value). The approach is tested by an implementation on the US Navy’s operational global data assimilation system and global and limited area numerical weather prediction models. The resulting system is evaluated by month long analysis-forecast experiments. It is found that REG DA can provide improved global forecasts with the largest improvements observed for Hurricane Sandy and frontal passages over the central plains. This result suggests that operational NWP centers that produce both global and regional forecast products could potentially improve their global forecasts without a significant increase in computational resources by implementing the proposed approach. Next, we employ local linear, spatial spectral, and Lorenz-curve based diagnostics to investigate the dynamics of uncertainty in global numerical weather forecasts in the NH extratropics. The diagnostics are applied to ensembles in the THORPEX Interactive Grand Global Ensemble (TIGGE). The initial growth of uncertainty is found to be the fastest at the synoptic scales (zonal wave numbers 7-9) most sensitive to baroclinic instability. At later forecast times, the saturation of uncertainties at the synoptic scales and the longer sustainable growth of uncertainty at the large scales lead to a gradual shift of the wave number of the dominant uncertainty towards zonal wave number 5. At the sub-synoptic scales, errors saturate as predicted by Lorenz’s classic theory. While the ensembles capture the general characteristics of the uncertainty dynamics efficiently, there are locations where the predicted magnitude and structure of uncertainty have considerable time-mean errors. In addition, the magnitude of systematic errors in the prediction of the uncertainty increases with increasing forecast time. These growing systematic errors are dominated by errors in the prediction of low frequency changes in the large scale flow. Advisors/Committee Members: Szunyogh, Istvan (advisor), Saravanan, Ramalingam (committee member), Korty, Robert L (committee member), Heltand, Robert D (committee member).

Subjects/Keywords: data assimilation; numerical weather prediction; ensemble forecasting; forecast uncertainty

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APA (6^th Edition):

Herrera, M. A. (2016). Techniques for the Improvement of Numerical Weather Prediction: Investigating the Dynamics of Forecast Uncertainty and the Implementation of Regionally Enhanced Global Data Assimilation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/159097

Chicago Manual of Style (16^th Edition):

Herrera, Michael Aaron. “Techniques for the Improvement of Numerical Weather Prediction: Investigating the Dynamics of Forecast Uncertainty and the Implementation of Regionally Enhanced Global Data Assimilation.” 2016. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/159097.

MLA Handbook (7^th Edition):

Herrera, Michael Aaron. “Techniques for the Improvement of Numerical Weather Prediction: Investigating the Dynamics of Forecast Uncertainty and the Implementation of Regionally Enhanced Global Data Assimilation.” 2016. Web. 16 Jan 2021.

Vancouver:

Herrera MA. Techniques for the Improvement of Numerical Weather Prediction: Investigating the Dynamics of Forecast Uncertainty and the Implementation of Regionally Enhanced Global Data Assimilation. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/159097.

Council of Science Editors:

Herrera MA. Techniques for the Improvement of Numerical Weather Prediction: Investigating the Dynamics of Forecast Uncertainty and the Implementation of Regionally Enhanced Global Data Assimilation. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/159097

Texas A&M University

20. Herrera, Michael Aaron. An Investigation of the Dynamics of Forecast Errors and Its Representation in the THORPEX Interactive Grand Global Ensemble (TIGGE).

Degree: MS, Atmospheric Sciences, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/154177

► We employ local linear diagnostics to investigate the efficiency of an ensemble in capturing the space and magnitude of forecast uncertainties. In this study, we… (more)

Subjects/Keywords: TIGGE; Forecast Error; NWP

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APA (6^th Edition):

Herrera, M. A. (2014). An Investigation of the Dynamics of Forecast Errors and Its Representation in the THORPEX Interactive Grand Global Ensemble (TIGGE). (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/154177

Chicago Manual of Style (16^th Edition):

Herrera, Michael Aaron. “An Investigation of the Dynamics of Forecast Errors and Its Representation in the THORPEX Interactive Grand Global Ensemble (TIGGE).” 2014. Masters Thesis, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/154177.

MLA Handbook (7^th Edition):

Herrera, Michael Aaron. “An Investigation of the Dynamics of Forecast Errors and Its Representation in the THORPEX Interactive Grand Global Ensemble (TIGGE).” 2014. Web. 16 Jan 2021.

Vancouver:

Herrera MA. An Investigation of the Dynamics of Forecast Errors and Its Representation in the THORPEX Interactive Grand Global Ensemble (TIGGE). [Internet] [Masters thesis]. Texas A&M University; 2014. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/154177.

Council of Science Editors:

Herrera MA. An Investigation of the Dynamics of Forecast Errors and Its Representation in the THORPEX Interactive Grand Global Ensemble (TIGGE). [Masters Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/154177

Texas A&M University

21. Li, Wei. A Climatology of Tropical Anvil and Its Relationship to the Large-Scale Circulation.

Degree: PhD, Atmospheric Sciences, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7340

► This dissertation uses multiple tools to investigate tropical anvil, i.e., thick, non-precipitating cloud associated with deep convection with the main objectives to provide a climatology… (more)

▼ This dissertation uses multiple tools to investigate tropical anvil, i.e., thick, non-precipitating cloud associated with deep convection with the main objectives to provide a climatology of tropics-wide anvil properties and a better understanding of anvil formation, and to provide a more realistic assessment of the radiative impact of tropical anvil on the large-scale circulation. Based on 10 years (1998-2007) of observations, anvil observed by the Tropical Rainfall Measuring Mission (TRMM) Precipitation (PR) shows significant geographical variations, which can be linked to variations in the parent convection. Strong upper level wind shear appears to assist the generation of anvil and may further explain the different anvil statistics over land and ocean. Variations in the large-scale environment appear to play a more important role in anvil production in regions where convection regularly attains heights greater than 7 km. For regions where convection is less deep, variations in the depth of the convection and the large-scale environment likely contribute more equally to anvil generation. Anvil radiative heating profiles are estimated by extrapolating millimeter cloud radar (MMCR) radiative properties from Manus to the 10-year TRMM PR record. When the unconditional anvil areal coverage is taken into account, the anvil radiative heating becomes quite weak, increasing the PR latent heating profile by less than 1 percent at mid and upper levels. Stratiform rain and cirrus radiative heating contributions increase the upper level latent heating by 12 percent. This tropical radiative heating only slightly enhances the latent heating driven model response throughout the tropics, but more significantly over the East Pacific. These modest circulation changes suggest that previous studies may have overemphasized the importance of radiative heating in terms of Walker and Hadley circulation variations. Further, the relationship of cloud radiative heating to latent heating needs to be taken into account for more realistic studies of cloud radiative forcing on the large-scale circulation. Advisors/Committee Members: Schumacher, Courtney (advisor), Nasiri, Shaima L. (committee member), Thomas, Debbie (committee member), Saravanan, Ramalingam (committee member), Kraucunas, Ian (committee member).

Subjects/Keywords: Climatology; Tropical anvil; Large-Scale circulation

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APA (6^th Edition):

Li, W. (2011). A Climatology of Tropical Anvil and Its Relationship to the Large-Scale Circulation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7340

Chicago Manual of Style (16^th Edition):

Li, Wei. “A Climatology of Tropical Anvil and Its Relationship to the Large-Scale Circulation.” 2011. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7340.

MLA Handbook (7^th Edition):

Li, Wei. “A Climatology of Tropical Anvil and Its Relationship to the Large-Scale Circulation.” 2011. Web. 16 Jan 2021.

Vancouver:

Li W. A Climatology of Tropical Anvil and Its Relationship to the Large-Scale Circulation. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7340.

Council of Science Editors:

Li W. A Climatology of Tropical Anvil and Its Relationship to the Large-Scale Circulation. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7340

22. Balaguru, Karthik. Barrier Layers of the Atlantic Warm Pool: Formation Mechanism and Influence on Weather and Climate.

Degree: PhD, Oceanography, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9214

► The aim of this research is to study the formation mechanism of Barrier Layers (BL) in the western tropical Atlantic and their influence on the… (more)

▼ The aim of this research is to study the formation mechanism of Barrier Layers (BL) in the western tropical Atlantic and their influence on the tropical Atlantic climate at both short and long timescales. Many Coupled General Circulation Models (CGCMs) tend to overestimate the salinity in the Atlantic warm pool or the Northwestern Tropical Atlantic (NWTA) and underestimate the surface salinity in the subtropical salinity maxima region. Most of these models also suffer from a seasurface temperature (SST) bias in the NWTA region, leading to suggestions that the upper ocean salinity stratification may need to be improved in order to improve the BL simulations and thus the SST through BL-SST-Intertropical Convergence Zone (ITCZ) feedbacks. We used a CGCM to perform a set of idealized numerical experiments to understand the sensitivity of the BL and consequently SST in the NWTA region to freshwater flux and hence the upper ocean salinity strati cation. We find that the BL of the western tropical Atlantic is quite sensitive to upper ocean salinity changes in the Amazon River discharge region and the subtropical salinity maxima region. The BL phenomenon is further manifested by the formation of winter temperature inversions in our model simulations. However, in the region of improved BL simulation, the SST response is not statistically significant. SST response to Tropical Cyclones (TCs) is studied for the Atlantic region using a high-resolution coupled regional climate model (CRCM) and observational data sets. The presence of a BL, defined as the layer below the mixed layer that separates the base of the isothermal layer from the base of the isohaline layer, is found to modulate the SST response. The amplitude of TC-induced surface cooling is reduced by more than 35 percent in the presence of a BL, as a consequence of the weak thermal stratification. Furthermore, in locations when the BL exhibits a temperature inversion, TC-induced mixing can result in weak surface warming. BLs considerably reduce the rightward bias for tropical storms, but the effect is less conspicuous for TCs. The enthalpy flux into the atmosphere at the air-sea interface is enhanced by 16 percent and the increase in upper ocean potential energy due to TC-induced mixing is reduced by 25 percent in the presence of BLs. The results from the coupled model are supported by an observational analysis performed using re-analysis data sets, as well as data from Argo floats and TRMM satellite. As previous modeling and observational studies have indicated that the surface cooling caused by TC-induced mixing acts as a negative feedback for its intensity, results from our study suggest that BLs may have potential implications for TC intensity prediction. Advisors/Committee Members: Chang, Ping (advisor), Saravanan, Ramalingam (committee member), Giese, Benjamin (committee member), Hetland, Robert (committee member).

Subjects/Keywords: Barrier Layers; Tropical Atlantic; Hurricanes

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APA (6^th Edition):

Balaguru, K. (2011). Barrier Layers of the Atlantic Warm Pool: Formation Mechanism and Influence on Weather and Climate. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9214

Chicago Manual of Style (16^th Edition):

Balaguru, Karthik. “Barrier Layers of the Atlantic Warm Pool: Formation Mechanism and Influence on Weather and Climate.” 2011. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9214.

MLA Handbook (7^th Edition):

Balaguru, Karthik. “Barrier Layers of the Atlantic Warm Pool: Formation Mechanism and Influence on Weather and Climate.” 2011. Web. 16 Jan 2021.

Vancouver:

Balaguru K. Barrier Layers of the Atlantic Warm Pool: Formation Mechanism and Influence on Weather and Climate. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9214.

Council of Science Editors:

Balaguru K. Barrier Layers of the Atlantic Warm Pool: Formation Mechanism and Influence on Weather and Climate. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9214

23. Ray, Sulagna. El Niño Southern Oscillation Variability from 1871-2008.

Degree: PhD, Oceanography, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10482

► The variation of El Nino Southern Oscillation (ENSO) events from the mid-nineteenth century until the beginning of the twenty-first century is explored using an ocean… (more)

▼ The variation of El Nino Southern Oscillation (ENSO) events from the mid-nineteenth century until the beginning of the twenty-first century is explored using an ocean reanalysis. Decadal variability and trends in the strength, frequency, duration, and propagation direction of ENSO events is investigated. The hypothesis that there are different types of ENSO and that the location of ENSO is shifting to the west Pacific is also studied. The study uses the latest version of an ocean reanalysis, called SODA 2.2.4 (Simple Ocean Data Assimilation), which covers the period from 1871 through 2008. The reanalysis uses an eddy-permitting resolution model of the ocean forced with boundary conditions available from an atmospheric reanalysis that covers the same period. SODA 2.2.4 assimilates all available hydrographic and surface marine observations of temperature and salinity to produce a "best estimate" of the ocean state in terms of temperature, current, salinity, and sea surface height. A new index based on the first moment of anomalous sea surface temperature over the equatorial Pacific is used to describe the location and strength of warm and cold events. The results show strong decadal variability in the strength of El Nino events but little trend during the period of 1871-2008. The strength of La Nina events has neither prominent decadal variation nor a trend. The index also documents changes in frequency, duration, and location of ENSO events. The study shows that the frequency of El Nino varies considerably over the record. Given the large variance in the period of ENSO it is difficult to reliably determine if there has been a change in the period of El Nino events. The location of warming during El Nino can be described by a normal distribution centered at about 140 degrees W. The strength and frequency of ENSO events have very little trend indicating negligible impact from global warming. Advisors/Committee Members: Giese, Benjamin (advisor), Chang, Ping (committee member), Stoessel, Achim (committee member), Saravanan, Ramalingam (committee member).

Subjects/Keywords: El Niño; Climate Change; El Niño variability

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APA (6^th Edition):

Ray, S. (2012). El Niño Southern Oscillation Variability from 1871-2008. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10482

Chicago Manual of Style (16^th Edition):

Ray, Sulagna. “El Niño Southern Oscillation Variability from 1871-2008.” 2012. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10482.

MLA Handbook (7^th Edition):

Ray, Sulagna. “El Niño Southern Oscillation Variability from 1871-2008.” 2012. Web. 16 Jan 2021.

Vancouver:

Ray S. El Niño Southern Oscillation Variability from 1871-2008. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10482.

Council of Science Editors:

Ray S. El Niño Southern Oscillation Variability from 1871-2008. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10482

24. Satterfield, Elizabeth A. Linear Diagnostics to Assess the Performance of an Ensemble Forecast System.

Degree: PhD, Atmospheric Sciences, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8258

► The performance of an ensemble prediction system is inherently flow dependent. This dissertation investigates the flow dependence of the ensemble performance with the help of… (more)

▼ The performance of an ensemble prediction system is inherently flow dependent. This dissertation investigates the flow dependence of the ensemble performance with the help of linear diagnostics applied to the ensemble perturbations in a small local neighborhood of each model grid point location ℓ. A local error covariance matrix Pℓ is defined for each local region and the diagnostics are applied to the linear space Sℓ defined by the range of the ensemble based estimate of Pℓ. The particular diagnostics are chosen to help investigate the ability of Sℓ to efficiently capture the space of true forecast or analysis uncertainties, accurately predict the magnitude of forecast or analysis uncertainties, and to distinguish between the importance of different state space directions. Additionally, we aim to better understand the roots of the underestimation of the magnitude of uncertainty by the ensemble at longer forecast lead times. Numerical experiments are carried out with an implementation of the Local Ensemble Transform Kalman Filter (LETKF) data assimilation system on a reduced (T62L28) resolution version of the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS). Both simulated observations under the perfect model scenario and observations of the real atmosphere are used in these experiments. It is found that (i) paradoxically, the linear space Sℓ provides an increasingly better estimate of the space of forecast uncertainties as the time evolution of the ensemble perturbations becomes more nonlinear with increasing forecast time, (ii) Sℓ provides a more reliable linear representation of the space of forecast uncertainties for cases of more rapid error growth, (iii) the E-dimension is a reliable predictor of the performance of Sℓ in predicting the space of forecast uncertainties, (iv) the ensemble grossly underestimates the forecast error variance in Sℓ, (v) when realistic observation coverage is used, the ensemble typically overestimates the uncertainty in the leading eigen-directions of ˆP ℓ and underestimates the uncertainty in the trailing directions at analysis time and underestimates the uncertainty in all directions by the 120-hr forecast lead time, and (vi) at analysis time, with a constant covariance inflation factor, the ensemble typically underestimates uncertainty in densely observed regions and overestimates the uncertainty in sparsely observed regions. Advisors/Committee Members: Szunyogh, Istvan (advisor), Saravanan, Ramalingam (committee member), North, Gerald (committee member), Genton, Marc (committee member).

Subjects/Keywords: Predictability; Ensemble Forecasting

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APA (6^th Edition):

Satterfield, E. A. (2011). Linear Diagnostics to Assess the Performance of an Ensemble Forecast System. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8258

Chicago Manual of Style (16^th Edition):

Satterfield, Elizabeth A. “Linear Diagnostics to Assess the Performance of an Ensemble Forecast System.” 2011. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8258.

MLA Handbook (7^th Edition):

Satterfield, Elizabeth A. “Linear Diagnostics to Assess the Performance of an Ensemble Forecast System.” 2011. Web. 16 Jan 2021.

Vancouver:

Satterfield EA. Linear Diagnostics to Assess the Performance of an Ensemble Forecast System. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8258.

Council of Science Editors:

Satterfield EA. Linear Diagnostics to Assess the Performance of an Ensemble Forecast System. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8258

25. Han, Fan. A Morphing-based Technique for the Verification of Deterministic and Ensemble Precipitation Forecasts.

Degree: PhD, Atmospheric Sciences, 2017, Texas A&M University

URL: http://hdl.handle.net/1969.1/161662

► A new morphing based technique is proposed for the verification of deterministic precipitation forecasts. It provides accurate estimates of the components of the precipitation forecast… (more)

Subjects/Keywords: Precipitation; Verification; Predictability

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APA (6^th Edition):

Han, F. (2017). A Morphing-based Technique for the Verification of Deterministic and Ensemble Precipitation Forecasts. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/161662

Chicago Manual of Style (16^th Edition):

Han, Fan. “A Morphing-based Technique for the Verification of Deterministic and Ensemble Precipitation Forecasts.” 2017. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/161662.

MLA Handbook (7^th Edition):

Han, Fan. “A Morphing-based Technique for the Verification of Deterministic and Ensemble Precipitation Forecasts.” 2017. Web. 16 Jan 2021.

Vancouver:

Han F. A Morphing-based Technique for the Verification of Deterministic and Ensemble Precipitation Forecasts. [Internet] [Doctoral dissertation]. Texas A&M University; 2017. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/161662.

Council of Science Editors:

Han F. A Morphing-based Technique for the Verification of Deterministic and Ensemble Precipitation Forecasts. [Doctoral Dissertation]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/161662

26. Verma, Tarun. Role of Ocean-Atmosphere Coupling in Regional Climatic Impacts of Anthropogenic Sulfate Aerosols.

Degree: PhD, Atmospheric Sciences, 2017, Texas A&M University

URL: http://hdl.handle.net/1969.1/173212

► Using a suite of coupled and uncoupled climate model experiments, we explore the impacts of anthropogenic sulfate aerosols on tropical Pacific climate and its variability.… (more)

▼ Using a suite of coupled and uncoupled climate model experiments, we explore the impacts of anthropogenic sulfate aerosols on tropical Pacific climate and its variability. The role of sea surface temperature (SST), ocean dynamics, and ocean-atmosphere interaction in climate response to aerosols is examined by appropriately choosing the ocean component namely, full ocean general circulation model (OGCM), slab ocean model (SOM) or prescribed climatological SST. The ensemble of shorter responses versus a long-term response highlights processes and coupled feedbacks that are active on seasonal-interannual timescales versus on multi-decadal timescales. We find that an abrupt increase in tropospheric sulfate aerosols gives rise to El Niño like warming of the eastern tropical Pacific on seasonal-interannual timescales. Dynamical interaction between the ocean and the atmosphere causes this equatorial warming, whereas the thermodynamic interaction is responsible for the off-equatorial warming. These two interactions are related to the presence of Bjerknes feedback over the equator versus the off-equatorial WES (Wind-Evaporation-SST) feedback in the tropical climate system. In long-term, ocean dynamics will remove the initial tropical warming leaving a weaker and negative SST in response to increased aerosols in the fully-coupled case. Absence of ocean dynamics in the partially-coupled case, on the other hand, will lead to amplification of the off-equatorial warming via positive WES feedback. These coupled feedbacks, therefore, control the intertropical convergence zone (ITCZ) shift in response to aerosols over the eastern tropical Pacific. In this study, we also identify a cloud microphysics based mechanism for the high cloud increase over the tropical Indian Ocean. This regional increase in high clouds results in local net positive radiative forcing in comparison to negative forcing elsewhere on the globe. Advisors/Committee Members: Saravanan, Ramalingam (advisor), Chang, Ping (committee member), North, Gerald R (committee member), Jun, Mikyoung (committee member).

Subjects/Keywords: Aerosols; El Niño; ocean-atmosphere interaction; tropical Pacific climate; Walker cell; Bjerknes feedback; WES feedback; high clouds

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APA (6^th Edition):

Verma, T. (2017). Role of Ocean-Atmosphere Coupling in Regional Climatic Impacts of Anthropogenic Sulfate Aerosols. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/173212

Chicago Manual of Style (16^th Edition):

Verma, Tarun. “Role of Ocean-Atmosphere Coupling in Regional Climatic Impacts of Anthropogenic Sulfate Aerosols.” 2017. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/173212.

MLA Handbook (7^th Edition):

Verma, Tarun. “Role of Ocean-Atmosphere Coupling in Regional Climatic Impacts of Anthropogenic Sulfate Aerosols.” 2017. Web. 16 Jan 2021.

Vancouver:

Verma T. Role of Ocean-Atmosphere Coupling in Regional Climatic Impacts of Anthropogenic Sulfate Aerosols. [Internet] [Doctoral dissertation]. Texas A&M University; 2017. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/173212.

Council of Science Editors:

Verma T. Role of Ocean-Atmosphere Coupling in Regional Climatic Impacts of Anthropogenic Sulfate Aerosols. [Doctoral Dissertation]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/173212

Texas A&M University

27. Casey, Sean P. An Assessment of Factors Limiting Tropical Congestus Cloud-Top Heights.

Degree: PhD, Atmospheric Sciences, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7396

► binding of either tyrosine or 6MPH4 alone does not change the coordination. However, when both tyrosine and 6MPH4 are bound, the active site becomes 5-coordinate,… (more)

▼ binding of either tyrosine or 6MPH4 alone does not change the coordination. However, when both tyrosine and 6MPH4 are bound, the active site becomes 5-coordinate, creating an open site for reaction with O2. Investigation of the kinetics of oxygen reactivity of TyrH complexes in the absence and presence of tyrosine and/or 6MPH4 indicated that there is a significant enhancement in reactivity in the 5-coordinate complex in comparison to the 6-coordinate form. Similar investigations with E332A TyrH showed that Glu332 residue plays a role in directing the protonation of the bridged complex that forms prior to the formation of Fe(IV)O. Rapid chemical quench analyses of DOPA formation showed a burst of product formation, suggesting a slow product release step. Steady-state viscosity experiments established a diffusional step as being significantly rate-limiting. Further studies with stopped-flow spectroscopy indicated that the rate of TyrH reaction is determined by a combination of a number of physical and chemical steps. Investigation of the NO complexes of TyrH by means of optical absorption, electron paramagnetic resonance (EPR) and electron spin echo envelope modulation (ESEEM) techniques revealed the relative positions of the substrate and cofactor with respect to NO, an O2 mimic, and provided further insight into how the active site is tuned for catalytic reactivity upon substrate and cofactor binding. The second theory is that a decreased vertical temperature lapse rate, dT/dp, would slow cloud growth, creating a mode of cloud-top heights at the stable layer as clouds lose buoyancy. The signal for lapse rate changes in the AIRS data, however, is not as strong as the signal for RH differences. Near 600-400 hPa, roughly the region where congestus cloud-top heights are located, no significant difference in lapse rates is noted between congestus and deep clouds; in fact, the mean values suggest that congestus clouds appear in more unstable atmospheres than deep clouds. Only slight differences in temperature and lapse rate are noted in ERA data as well. These results suggest that drier air may play a greater role in limiting congestus cloud-top heights than increased atmospheric stability. Five years of relative humidity (RH) observations from the Atmospheric Infrared Sounder (AIRS) instrument aboard the Aqua satellite are then analyzed to identify areas of anomalously dry air between 600 and 400 hPa over deep convective regions of the tropical oceans. Back trajectories are then calculated for each observed parcel. Advisors/Committee Members: Dessler, Andrew E. (advisor), Schumacher, Courtney (committee member), Saravanan, Ramalingam (committee member), Filippi, Anthony M. (committee member).

Subjects/Keywords: Tropical Convection; Dry Air Layers; Congestus Clouds

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

APA (6^th Edition):

Casey, S. P. (2010). An Assessment of Factors Limiting Tropical Congestus Cloud-Top Heights. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7396

Chicago Manual of Style (16^th Edition):

Casey, Sean P. “An Assessment of Factors Limiting Tropical Congestus Cloud-Top Heights.” 2010. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7396.

MLA Handbook (7^th Edition):

Casey, Sean P. “An Assessment of Factors Limiting Tropical Congestus Cloud-Top Heights.” 2010. Web. 16 Jan 2021.

Vancouver:

Casey SP. An Assessment of Factors Limiting Tropical Congestus Cloud-Top Heights. [Internet] [Doctoral dissertation]. Texas A&M University; 2010. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7396.

Council of Science Editors:

Casey SP. An Assessment of Factors Limiting Tropical Congestus Cloud-Top Heights. [Doctoral Dissertation]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7396

Texas A&M University

28. Ghosh, Souparno. Copula Based Hierarchical Bayesian Models.

Degree: PhD, Statistics, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7160

► The main objective of our study is to employ copula methodology to develop Bayesian hierarchical models to study the dependencies exhibited by temporal, spatial and… (more)

▼ The main objective of our study is to employ copula methodology to develop Bayesian hierarchical models to study the dependencies exhibited by temporal, spatial and spatio-temporal processes. We develop hierarchical models for both discrete and continuous outcomes. In doing so we expect to address the dearth of copula based Bayesian hierarchical models to study hydro-meteorological events and other physical processes yielding discrete responses. First, we present Bayesian methods of analysis for longitudinal binary outcomes using Generalized Linear Mixed models (GLMM). We allow flexible marginal association among the repeated outcomes from different time-points. An unique property of this copula-based GLMM is that if the marginal link function is integrated over the distribution of the random effects, its form remains same as that of the conditional link function. This unique property enables us to retain the physical interpretation of the fixed effects under conditional and marginal model and yield proper posterior distribution. We illustrate the performance of the posited model using real life AIDS data and demonstrate its superiority over the traditional Gaussian random effects model. We develop a semiparametric extension of our GLMM and re-analyze the data from the AIDS study. Next, we propose a general class of models to handle non-Gaussian spatial data. The proposed model can deal with geostatistical data that can accommodate skewness, tail-heaviness, multimodality. We fix the distribution of the marginal processes and induce dependence via copulas. We illustrate the superior predictive performance of our approach in modeling precipitation data as compared to other kriging variants. Thereafter, we employ mixture kernels as the copula function to accommodate non-stationary data. We demonstrate the adequacy of this non-stationary model by analyzing permeability data. In both cases we perform extensive simulation studies to investigate the performances of the posited models under misspecification. Finally, we take up the important problem of modeling multivariate extreme values with copulas. We describe, in detail, how dependences can be induced in the block maxima approach and peak over threshold approach by an extreme value copula. We prove the ability of the posited model to handle both strong and weak extremal dependence and derive the conditions for posterior propriety. We analyze the extreme precipitation events in the continental United States for the past 98 years and come up with a suite of predictive maps. Advisors/Committee Members: Mallick, Bani K. (advisor), Huang, Jianhua (committee member), Genton, Marc G. (committee member), Saravanan, Ramalingam (committee member).

Subjects/Keywords: Hierarchical model; Copula; Geostatistics; Extreme value processes

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

APA (6^th Edition):

Ghosh, S. (2010). Copula Based Hierarchical Bayesian Models. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7160

Chicago Manual of Style (16^th Edition):

Ghosh, Souparno. “Copula Based Hierarchical Bayesian Models.” 2010. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7160.

MLA Handbook (7^th Edition):

Ghosh, Souparno. “Copula Based Hierarchical Bayesian Models.” 2010. Web. 16 Jan 2021.

Vancouver:

Ghosh S. Copula Based Hierarchical Bayesian Models. [Internet] [Doctoral dissertation]. Texas A&M University; 2010. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7160.

Council of Science Editors:

Ghosh S. Copula Based Hierarchical Bayesian Models. [Doctoral Dissertation]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7160

Texas A&M University

29. Myoung, Boksoon. Interannual variability of summer precipitation in Texas and its implication to summer drought.

Degree: PhD, Atmospheric Sciences, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1422

► Since Texas normally receives most of its precipitation in the warm season, precipitation deficits in summertime may bring serious agricultural and hydrological disasters. While the… (more)

▼ Since Texas normally receives most of its precipitation in the warm season, precipitation deficits in summertime may bring serious agricultural and hydrological disasters. While the underlying physical processes of summer precipitation deficit and drought are unclear, they can be understood in terms of convective instability. This research is designed to investigate how convective instability influences monthly mean precipitation in Texas in the summertime and to examine the modulation of convective instability and precipitation by upper-level circulations, soil moisture, vertical motion, and low-tropospheric warm air transport using NCEP/NCAR reanalysis data. Statistical approaches including correlation analysis, multiple linear regression analysis and back trajectory analysis were used to reveal the underlying dynamics of their linkage and causality. The results show that warming at 700 mb and surface dryness result in excessive convective inhibition (CIN), leading to precipitation deficits on a monthly time-scale. Temperature at 700 mb (Tlt) and surface dewpoint have little correlation suggesting different processes contribute to warming at 700 mb and surface dryness, respectively. Correlation analysis among the surface variables emphasizes the role of soil moisture on the dewpoint and thermodynamics at the surface. Back trajectory analysis indicates that a significant contributor to warming at 700 mb is the inversion caused by warm air transport from the Rocky Mountains and the Mexican Plateau where the surface potential temperature is greater than 307.5K rather than by subsidence. It was found that downward motion and warm air transport are enhanced in Texas when upper-level anticyclonic circulation develops in the southern US. Upper-level anticyclonic circulations in the southern US strongly affect Texas summertime precipitation by modulating the principal processes as follows. They increase CIN not only by enhancing warm air transport from the high terrain but also by suppressing occurrence of disturbances. The resulting reduced precipitation and dry soil significantly modulate surface conditions, which elevates CIN and decreases precipitation. The aforementioned chain-reaction of upper-level anticyclone influences can be understood in the context of CIN. Advisors/Committee Members: Nielsen-Gammon, John (advisor), Carey, Larry (committee member), Chang, Ping (committee member), North, Gerald (committee member), Saravanan, Ramalingam (committee member), Schumacher, Courtney (committee member).

Subjects/Keywords: Texas; drought; precipitation variability

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

APA (6^th Edition):

Myoung, B. (2009). Interannual variability of summer precipitation in Texas and its implication to summer drought. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1422

Chicago Manual of Style (16^th Edition):

Myoung, Boksoon. “Interannual variability of summer precipitation in Texas and its implication to summer drought.” 2009. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-1422.

MLA Handbook (7^th Edition):

Myoung, Boksoon. “Interannual variability of summer precipitation in Texas and its implication to summer drought.” 2009. Web. 16 Jan 2021.

Vancouver:

Myoung B. Interannual variability of summer precipitation in Texas and its implication to summer drought. [Internet] [Doctoral dissertation]. Texas A&M University; 2009. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1422.

Council of Science Editors:

Myoung B. Interannual variability of summer precipitation in Texas and its implication to summer drought. [Doctoral Dissertation]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1422

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