Physical Sciences and Mathematics Commons^™

Comparative Assessment Of Downscaling Methods And Application Towards Analysis Of Climate Change Impact On Urban Regions, Markus Eichenbaum

Electronic Thesis and Dissertation Repository

Global climate models (GCM) are sophisticated numerical models used to make long term climate projections. However, the resolution of their output is too coarse for climate change related local impact studies on urban regional scales. Downscaling efforts are taken to address this and increase GCM projection resolution. Physical Scaling (SP) downscaling methodology attempts to incorporate the physical basis of dynamical downscaling efforts with the computational efficiency of statistical methods. In this study, North American Regional Reanalysis surface skin temperature and precipitation data for a 1°x1° region centered on Houston, TX are downscaled to a resolution of 500m via SP and …

Hydrological And Paleoclimate Analysis Of A Pinyon-Juniper And Fen-Dominated Watershed On The Windy Ridge Mega-Landslide, Joel Frederick Barker

Theses and Dissertations

Water BudgetThis chapter documents the hydrologic analysis of a watershed within the Windy Ridge mega-landslide of Central Utah to (1) create a water budget and (2) place a quantitative limit on the magnitude of climatic changes documented by Shurtliff et al. (2017) and Hudson et al. (2019). (1) A water budget was calculated over the last four years using instrumentation and weather stations both within and surrounding the watershed, In terms of precipitation input, 85% is released by the evapotranspiration of the Pinyon-Juniper forest, 4% discharges as surface water from the base of the watershed, and 11 % infiltrates the …

Spatial And Temporal Mapping Of Distributed Precipitation, Surface And Groundwater Stable Isotopes Enables Insights Into Hydrologic Processes Operating At A Catchment Scale, Alison Cole

Masters Theses

Isotopic analyses of d¹⁸O and d²H of water through the hydrologic cycle have allowed hydrologists to make better interpretations related to climate and relationships between precipitation, surface water, and groundwater. In this study 394 precipitation samples 1917 surface water samples and 1405 groundwater samples across Massachusetts was used to create an isoscape for each respective water. All samples have been collected by volunteers throughout Massachusetts. A state meteoric water line: d²H = 7.7*d¹⁸O + 9.8, surface water line: d²H = 5.7*d¹⁸O – 4.2, and groundwater line: d^{2 …}

Hourly Precipitation Climatology Of The Southeast United States, Vincent Brown

LSU Doctoral Dissertations

Precipitation changes are one of the most important potential outcomes of a warming climate because of how essential it is to society and ecosystems. Sub-daily precipitation time series provide more information on precipitation characteristics, particularly frequency, intensity, and duration compared to daily data. In a series of four peer-reviewed manuscripts, this research investigates sub-daily precipitation characteristics from a climatological perspective. The first study introduces a climatology of hourly precipitation for four first-order weather stations across Louisiana, explores possible changes in the hourly precipitation distribution, and links winter Gulf of Mexico sea surface temperatures to the frequency of hours with precipitation. …

Cool And Warm Season Climate Signals In Tree Rings From North America, Max Carl Arne Torbenson

Graduate Theses and Dissertations

Earlywood (EW) and latewood (LW) ring-width chronologies have become an increasingly important proxy in paleoclimate reconstructions. These subannual variables can provide estimates of past hydroclimate variability for seasonal windows that total ring-widths cannot resolve. The strength of the relationship between EW and LW series may influence what type of paleoclimate information is embedded within the tree-ring series. High correlations (> 0.70) between EW and LW are recorded for much of the continent but the magnitude of correlation varies greatly across space and species boundaries. Using four LW chronologies from shortleaf pine, the North American conifer species displaying the lowest EW-LW …

Ecological And Economic Implications Of Increased Storm Frequency And Severity For Boreal Lakes, Kathryn Warner

Electronic Theses and Dissertations

In boreal regions, increased precipitation events have been linked to increased concentrations of dissolved organic carbon (DOC), however less is known about the extent and implications of these events on lakes. We assessed the effects of precipitation events on six drinking water lakes in Maine, USA to better understand how DOC concentration and quality change in response to precipitation events. Our results revealed three types of responses: (1) an initial spike in DOC concentrations and quality metrics; (2) a sustained increase in DOC concentrations and quality metrics and; (3) no change during all sampling periods. Lake residence time was a …

Multi-Resolution Spatio-Temporal Change Analyses Of Hydro-Climatological Variables In Association With Large-Scale Oceanic-Atmospheric Climate Signals, Kazi Ali Tamaddun

UNLV Theses, Dissertations, Professional Papers, and Capstones

The primary objective of the work presented in this dissertation was to evaluate the change patterns, i.e., a gradual change known as the trend, and an abrupt change known as the shift, of multiple hydro-climatological variables, namely, streamflow, snow water equivalent (SWE), temperature, precipitation, and potential evapotranspiration (PET), in association with the large-scale oceanic-atmospheric climate signals. Moreover, both observed datasets and modeled simulations were used to evaluate such change patterns to assess the efficacy of the modeled datasets in emulating the observed trends and shifts under the influence of uncertainties and inconsistencies. A secondary objective of this study was to …

Utilization Of Remote Sensing Data For Estimation Of The Groundwater Storage Variation, Gaurang Mistry

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater is the most extracted raw material, with an average withdrawal rate of 982 km3 per year, where 70 percent of the total groundwater withdrawn is used for agriculture globally (Margat & van der Gun, 2013). With climate change and increased water demands in recent years, monitoring the changes in the groundwater storage is of the utmost importance. This thesis presents an analysis that determines the rates, trends, and directions where groundwater storage is going in Pakistan. It also correlates fluctuations in groundwater storage with variations in precipitation and agricultural productivity in the country. The overall objectives of this thesis …

Future Changes Of Hydroclimatic Extremes In Western North America Using A Large Ensemble: The Role Of Internal Variability, Mohammad Hasan Mahmoudi

Electronic Thesis and Dissertation Repository

Increases in the intensity and frequency of extreme events in Western North America (WNA) can cause significant socioeconomic problems and threaten existing infrastructure. In this study we analyze the impacts of climate change on hydroclimatic extremes and assess the role of internal variability over WNA, which collectively drain an area of about 1 million km². We used gridded observations and downscaled precipitation, maximum and minimum temperature from seven General Circulation Models (GCMs) that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5) and a large ensemble of CanESM2 model simulations (CanESM2-LE; 50 members) for this analysis. Spatial …

Spatio-Temporal Analysis Of Precipitation And Flood Data From South Carolina, Haigang Liu

Theses and Dissertations

Spatio-temporal data are everywhere: we encounter them on TV, in newspapers, on computer screens, on tablets, and on plain paper maps. As a result, researchers in di- verse areas are increasingly faced with the task of modeling geographically-referenced and temporally-correlated data. In this dissertation, we propose two different spa- tiotemporal models to capture the behavior of rainfall and flood data in the state of South Carolina.

Both models are built using a Bayesian hierarchical framework, which involves specifying the true underlying process in the first level and the spatio-temporal ran- dom effect in the second level of the hierarchy. The …

Precipitation And Coacervation In Polyelectrolyte-Colloid Systems, Fatih Comert

Doctoral Dissertations

Complex coacervation between oppositely charged polyelectrolytes (PEs) and colloids (i.e. micelles and proteins) has increasingly become popular due to the use of these materials in a range of applications including but not limited to personal care, biomaterials, protein purification, and food science. In taking advantage of complex coacervation, which is a liquid-liquid phase separation, precipitation has always represented a problem by introducing inhomogeneities, irreversibility and irreproducible kinetics. Therefore, understanding the dominant factors driving the formation of precipitates is important to control outcomes. In this work, we have performed comparative studies of coacervation and precipitation in model PE-colloid systems to investigate …

Convection-Permitting Ensemble Forecasts Of The 10-12 December 2013 Lake-Effect Snow Event: : Sensitivity To Microphysical, Planetary Boundary Layer, And Surface Layer Parameterizations, William Massey Bartolini

Legacy Theses & Dissertations (2009 - 2024)

Lake-effect snow (LeS) presents a substantial forecast challenge for convection-permitting models, due in part to uncertainties in the parameterization of microphysical (MP) and planetary boundary layer / surface layer (PBL/SL) processes. Here we focus on understanding these uncertainties for a LeS event that occurred during 10–12 December 2013 during the Ontario Winter Lake-effect Systems (OWLeS) field campaign. Throughout this event, long-lake-axis-parallel snowbands persisted downwind of the eastern shore of Lake Ontario, leading to snowfall accumulations as high as 105 cm (liquid precipitation equivalent of 64.5 mm) on the Tug Hill Plateau.

Precipitation Characteristics And Their Dependence On Data Resolution And Model Physics, Di Chen

Legacy Theses & Dissertations (2009 - 2024)

To fully characterize precipitation, one often needs not only the accumulative amount (A), but also its frequency (F), intensity (I) and duration (D). These characteristics have large impacts on Earth’s hydrologic cycle. Aiming for a comprehensive understanding, this dissertation investigates precipitation characteristics and their dependence on data resolution and model physics using observational datasets and comprehensive global climate models (GCMs).