Meteorology Commons^™

Convection Allowing Simulations Of Hail In Historical And Future Climate Epochs, Jillian Rose Goodin

Graduate Research Theses & Dissertations

This thesis investigates the potential impact of anthropogenic climate change on hail frequency and intensity, which poses a significant threat to life and property, accounting for annual insured losses of around $30 billion in the U.S. This approach uses convection-allowing dynamically-downscaled regional climate simulations using input data from NCAR's bias-corrected Community Earth System Model to simulate historical and projected future climate regimes under two greenhouse gas emission scenarios. A column maximum diameter hail diagnostic is simulated by the Weather Research and Forecasting regional climate model to identify instances of hail days and size to quantify changes in large hail frequency …

Historical And Potential Future Climate Of Extreme Daily Precipitation Over The Contiguous United States Using Convection-Permitting Simulations, Sylvia Stinnett

Graduate Research Theses & Dissertations

The impacts of anthropogenic climate change will be felt most strongly through changes in hazards such as extreme precipitation. The potential for extreme precipitation changes—both increases and decreases—may have significant societal impacts (e.g., agriculture production, loss of life and property). However, limited research has quantified future projected changes in extreme precipitation due to computational limitations and considerable time expenditure for convection-permitting simulations of substantial duration.This project sought to analyze changes in extreme daily precipitation—defined as the 99th percentile daily accumulated value—due to climate change in the contiguous United States (CONUS) using a dynamically downscaled and convection-permitting regional climate modeling framework. …

Climatology Of The Elevated Mixed Layer Over The Contiguous United States And Northern Mexico: 1979–2021, Margo Siciliano Andrews

Graduate Research Theses & Dissertations

Elevated mixed layers (EMLs) are an important influence on the severe convective storm climatology in the contiguous United States (CONUS), playing a role in storm generation, sustenance, and suppression. A function of the topography in the western CONUS and northern Mexico, EMLs are elevated layers of nearly dry adiabatic lapse rates and high potential temperature, typically with a capping inversion at their base. Although it is well-established that EMLs are primarily a warm-season phenomenon most frequent in the Great Plains, no research to date has examined their variability in-depth, or whether they have changed through time. This study creates an …

Weather-Related Carbon Monoxide Poisoning In The United States: 2000-2019, Bailey Raine Stevens

Graduate Research Theses & Dissertations

Carbon monoxide (CO) is a colorless, odorless gas that can cause injury or death if inhaled. CO is a frequent secondary hazard induced by the aftereffects of natural hazards as individuals, families, and communities will often seek alternative power sources for heating, cooking, lighting, and cleanup during the emergency and recovery phases of a disaster. These alternative power sources – such as generators, petrol heaters, and vehicles, exhaust CO – can ultimately build to toxic levels in enclosed areas. Ever-increasing environmental and societal changes combined with an aging infrastructure are increasing the odds of power failures during hazardous weather events, …

Trends In Observed And Simulated Radar Reflectivity For The 21st Century, Christopher Michael Battisto

Graduate Research Theses & Dissertations

The effects of climate change may influence the prevalence of regional atmospheric conditions supportive of hazardous convective weather (HCW). As a result, the possibility of an increase in the frequency, strength, and/or variability of thunderstorms and their high-impact hazards—including tornadoes, damaging winds, hail, and flash flood-producing downpours—has garnered much scientific and public interest. Radar reflectivity, which remotely assesses precipitation intensity, may be used to detect, track, catalog, and appraise HCW and their parent storms over broad spatiotemporal scales. Reflectivity may also be simulated with regional climate models, and recent, but limited, efforts using these simulation output have identified the potential …

Midwestern U.S. Diurnal Temperature Range: Spatial And Temporal Trends From 1900-2018, Kelly Ann Swaney

Graduate Research Theses & Dissertations

In the Corn Belt region of the United States, the twentieth century saw many land use changes as the land had been converted from the natural landscape to cropland. As the twentieth century progressed, numerous advancements occurred to increase the crop acreage, crop density, and amount of irrigated land. All of these changes contributed to higher rates of evapotranspiration, which put more moisture into the low levels of the atmosphere. This additional moisture played a role in changing the radiative fluxes and, as a result, the surface temperature. The Diurnal Temperature Range (DTR) is examined across the 1900 to 2018 …

Analysis Of Emissions Inventory Challenges Across The U.S. Supported By The Case Study Of Dekalb, Illinois, Using Clearpath, Emery Taylor Dhanens

Graduate Research Theses & Dissertations

The urgent need to address the destructive effects of climate change globally through mitigation and adaptation is clear. A useful tool for climate change mitigation is a greenhouse gas emissions inventory, which can be used to benchmark current emission levels and create future reduction goals. Emissions inventories in the United States are not currently required by the federal government, but many cities are nonetheless choosing to conduct these inventories and adopt greenhouse gas reduction goals. Inventory tools vary in terms of the methodologies behind emissions calculations, and previous studies have noted the comparability and consistency issue among inventories. This mixed-methods …

Environmental Discriminators For Significant Tornadoes And Hail In The U.S. Using Proximity Soundings, Cody Michael Converse

Graduate Research Theses & Dissertations

Over the last 50 years, the United States has experienced an increase in severe storm events that produced $1 billion in damages or greater. Much of this loss is attributed to significant tornadoes and hail associated with deep, moist convection. Improving forecasts for these significant events assist in mitigating the impacts of these events. Previous work has identified statistically significant environmental parameters associated with severe thunderstorms, but more research is needed in identifying statistically significant ingredients associated with environments that produce significant tornadoes and hail.

This thesis aims to answer the following question: “Can diagnostics commonly used to forecast for …

A Climatology Of Quasi-Linear Convective Systems In The U.S., Jacob Adam Strohm

Graduate Research Theses & Dissertations

Quasi-linear convective systems, or QLCSs, are a common, organized thunderstorm mode in the U.S. Over the last fifty years, severe weather research has focused on the supercell, but, recently, QLCSs have become an increasingly important area of study. Researchers and operational meteorologists realize that this morphology is difficult to forecast and may be responsible for a large proportion of the severe weather reports in the eastern two-thirds of the U.S. This study seeks to determine the degree to which QLCSs threaten humans and their assets by, first, assessing their climatology and, second, measuring their contribution to the severe report record. …