Atmospheric Sciences Commons^™

Influence Of Cloud-Radiative Forcing On Tropical Cyclone Development In Moderate Vertical Wind Shear, Jannetta C. Richardson

Electronic Theses & Dissertations (2024 - present)

This research seeks to better understand how cloud–radiative forcing (CRF) influences the structural evolution and intensity change of tropical cyclones (TCs) during the organizaional stage, with a particular focus on environments characterized by moderate vertical wind shear. While CRF has been shown to impact TC development during genesis and mature stages, its role during the transitional post-genesis phase—when TCs exhibit disorganized convection and are highly sensitive to environmental influences—remains poorly understood. Moreover, forecasting TC intensity in moderate shear environments continues to present substantial challenges, underscoring the need for focused investigation of TC development in the moderate-shear regime.

The Weather Research …

Deep Convection, Lightning, And Inertio-Gravity Waves: An Analysis Of Precipitation And Wave Dynamics In The Congo Basin, Stephen L. Solimine

Electronic Theses & Dissertations (2024 - present)

The lack of an extensive in situ observation network throughout equatorial Africa makes it difficult to monitor the Congo climate system. Model and reanalysis products have been used to fill informational gaps but often produce disparate results. To improve model representation of deep convection over the Congo, it’s important to first understand the influence of various thermodynamic and dynamic forces that may be underrepresented. Although satellite based remote sensing retrievals and reanalysis have their own set of limitations, they can offer a great deal of insight into the climate of regions otherwise lacking in observational networks.

The first section of …

Misoscale Vortices In The Eyewall Boundary Layer Of A Tropical Cyclone In A Large Eddy Simulation, Emily A. Lucy

Electronic Theses & Dissertations (2024 - present)

Since the late 1980s, there have been numerous observations of extreme updrafts, gusts, and small-scale rotation in the eyewall of tropical cyclones (TCs). Research aircraft, dropsondes, and, more recently, mobile radars have collected these observations, most often from within the boundary layer. Previous studies have documented dropsondes associated with extreme gusts and updrafts, while others have discussed specific incidents of misoscale features in tropical cyclones. Several high-resolution numerical simulations of TCs have documented similar features. This study uses one such simulation from Worsnop et al. (2017). A small but intense tropical cyclone in a quiescent environment is simulated.

This simulation …

Comparison Of Methane Emission Quantification Methods At Landfills In New York State, Alexandra M. Catena

Electronic Theses & Dissertations (2024 - present)

Greenhouse gas (GHG) emission increases are a consequence of global population rise and economic growth. It is well known that carbon dioxide is the dominant GHG by mass, but methane has received increasing attention recently due to its high warming potential and relatively short lifetime of about a decade. Methane has several different types of both natural and anthropogenic sources including wetlands, waste management, energy, agriculture and farming, and wildfires, which makes tracking and reducing methane emissions a complex problem. The emission rates of each of these sources are highly uncertain due to differing emission estimation methods, which can be …

The Large-Scale Flow Dynamics And Controls On Recurving Eastern North Pacific Tropical Cyclones, Alexander Kyle Mitchell

Electronic Theses & Dissertations (2024 - present)

While eastern North Pacific (EPAC) tropical cyclones (TCs) most often move westward over open water, a subset deviates from this typical path, recurving toward higher latitudes or making landfall along the North American coastline. Because such events are relatively rare, they have received less attention, despite their significant contributions to rainfall and wildfire activity across the southwestern United States. This dissertation identifies and characterizes the spatial variability of EPAC TC tracks, analyzes the synoptic environments associated with TC recurvature near the North American coast, presents a detailed case study of two recurving EPAC TCs from late September to early October …

Buoy-Based Eddy Covariance Drag Coefficient At A Near-Shore And Offshore Site, David P. Marcial

Electronic Theses & Dissertations (2024 - present)

An eddy covariance (EC) flux system was integrated onto a Navy Oceanographic Meteorological Automatic Device (NOMAD) floating lidar buoy fitted for measuring the offshore wind resource. The EC flux system consisted of two sonic anemometers and an inertial measurement unit that together provided high-frequency (10 Hz) motion-corrected wind measurements. To assess possible impacts of flow distortion, EC momentum fluxes (10 min) were calculated in gravity-aligned, natural, and planar fit (PF) coordinate frames. The buoy was anchored near the Martha’s Vineyard Coastal Observatory Air-Sea Interaction Tower (ASIT; near-shore) for validation of the buoy-based EC fluxes against the fixed tower measurements before …

Using Convolutional Neural Networks To Identify Rare Weather Events: Application To Kona Low Classifications With Large-Scale Wind Pattern, Anadhi Sharma

Electronic Theses & Dissertations (2024 - present)

Extreme events pose challenges in prediction on account of their low frequency and erratic nature. Among these events, Kona lows are rare subtropical cyclones that significantly impact the weather pattern of Hawaii, sometimes causing heavy rainfall, strong winds, and coastal flooding. In the past, studies have used traditional statistical methods such as synoptic climatology, regression analysis, and manual classification that rely on expert judgment to identify Kona lows; however, they often struggle to capture the complex spatial patterns of the Kona storms. Convolutional Neural Networks (CNNs) exhibit a property called translation invariance, which allows them to learn and recognize Kona …

"Assessment Of The Likelihood To Stay Below 2 Degree Celsius Warming: Combining Modeling And Scenario Uncertainty.", Peter M. Booker

Electronic Theses & Dissertations (2024 - present)

ABSTRACT

Uncertainty in how much the Earth will warm in response to rising atmospheric CO₂ concentrations remains a major challenge for climate science and policy. In particular, estimates of equilibrium climate sensitivity (ECS) and transient climate response (TCR) directly affect projections of global mean surface temperature (GMST) and the allowable carbon budget for limiting warming to 2°C by 2100.

This study assesses the performance of a two-layer energy balance model (EBM) in reproducing TCR and ECS values under CMIP6 forcing scenarios, with a focus on SSP2-4.5. EBM outputs are compared against General Circulation Models (GCMs), and agreement is evaluated using …

Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones

Graduate Theses/Dissertations

Karst landscapes are abundant in Missouri, with features such as caves, springs, and sinkholes that form through the dissolution of limestone. Leith Creek is a small stream in Polk County, Missouri fed by two springs and the shallow unconfined Springfield Plateau aquifer, a highly karstified aquifer which is made up of limestone and minor interbedded shale-mudstone units. To determine if Leith Creek is gaining or losing, stream flow, water chemistry and temperature sensors were monitored. Stream flow results required multiple visits to take measurements while temperature sensors required two visits, one to install the dataloggers and another to remove the …

Validating Atmospheric Freezing Level Heights Using Purdue University Weather Balloon Data, Danielle Harr

The Journal of Purdue Undergraduate Research

No abstract provided.

A Meteorological Investigation Of A Tornado- Producing, “Hybrid” Supercell-Multicell Storm Near Delphi, Indiana, On May 8, 2023, Evelyn Rose K. Girardi

The Journal of Purdue Undergraduate Research

No abstract provided.

Discrimination The Roles Of Anthropogenic Greenhouse Gases And Aerosols On Tropical Cyclone Frequency From Downscaling Cmip6 Models, George Gyabaah

Theses and Dissertations

Tropical cyclones (TCs) are devastating disasters, yet predicting their future activity remains highly uncertain. To better understand the impacts of different anthropogenic forcings, specifically greenhouse gases (GHG) and aerosols on the TCs, I downscaled the single forcing experiments of 11 CMIP6 models in the Columbia HAZard Model (CHAZ). This analysis focused on changes in the distribution of the North Atlantic (ATL) and Western North Pacific (WNP) basins and explored the shift in environmental variables that drive them. We then used the formulation of the genesis component of CHAZ as a constraint to quantify the relative contribution of each predictor relative …

Advancing S2s Precipitation Outlooks Through The Weather Regime-Gaussian Mixture Model Framework, Wei Zhang

Funded Research Records

No abstract provided.

An Integrated Study Of Aerosol Concentrations And Meteorological Conditions In El Paso Airshed Using Modeling And Instrumentation, Joscelyne Guzman-Gonzalez

Open Access Theses & Dissertations

Atmospheric aerosols are solid or liquid particles suspended in the atmosphere. Aerosols can be primary, which are directly emitted into the atmosphere, or secondary, which are formed when emitted gases undergo complex chemical reactions. Atmospheric aerosols can range from a few nanometers to tens of microns in diameter. Atmospheric aerosols play a significant role in climate; they can absorb or reflect heat, influencing temperature and weather patterns. Air quality is also affected by aerosols, which can have detrimental effects on human health, contributing to respiratory issues and other health problems. El Paso Texas is located at the south of the …

Modeling Hourly Storm Surges Using Deep Learning Techniques, Md Abu Zafor

Master's Theses

Storm surges cause coastal flooding, one of the most devastating coastal hazards. Accurate modeling of storm surges is essential for predicting and mitigating these impacts. Traditional approaches model surges at individual tide gauges and often focus on daily time scales, leading to data redundancy and limiting their ability to capture sub-daily variability. This study addresses these limitations using deep learning (DL) algorithms to model hourly surges simultaneously at multiple tide gauges along the U.S. East Coast and Gulf of Mexico. Three algorithms, Convolutional Neural Network (CNN), Long Short-Term Memory (LSTM), and a hybrid ConvLSTM are employed to model surges using …

Spatial Gap-Filling Of Himawari-8 Hourly Aod Products Using Machine Learning With Model-Based Aod And Meteorological Data: A Focus On The Korean Peninsula, Youjeong Youn, Seoyeon Kim, Seung Hee Kim, Yangwon Lee

Institute for ECHO Articles and Research

Given the complex spatiotemporal variability of aerosols, high-frequency satellite observations are essential for accurately mapping their distribution. However, optical remote sensing encounters difficulties in detecting Aerosol Optical Depth (AOD) over cloud-covered regions, creating data gaps that limit comprehensive environmental analysis. This study introduces a spatial gap-filling method for Himawari-8/Advanced Himawari Imager (AHI) hourly AOD data, using a Random Forest (RF) model that integrates meteorological variables and model-based AOD data. Developed and validated over South Korea from 1 January to 31 December 2019, the model effectively improved data coverage from 6% to 100%. The approach demonstrated high performance in blind tests, …

Climatological Trends And Effects Of Aerosols And Clouds On Large Solar Parks: Application Examples In Benban (Egypt) And Al Dhafrah (Uae), Harshal Dhake, Panagiotis Kosmopoulos, Antonis Mantakas, Yashwant Kashyap, Hesham El-Askary, Omar Elbadawy

Mathematics, Physics, and Computer Science Faculty Articles and Research

Solar energy production is vastly affected by climatological factors. This study examines the impact of two primary climatological factors, aerosols and clouds, on solar energy production at two of the world’s largest solar parks, Benban and Al Dhafrah Solar Parks, by using Earth observation data. Cloud microphysics were obtained from EUMETSAT, and aerosol data were obtained from the CAMS and assimilated with MODIS data for higher accuracy. The impact of both factors was analysed by computing their trends over the past 20 years. These climatological trends indicated the variations in the change in each of the factors and their resulting …

Predicting Cloud-To-Ground Lightning In The Western United States From The Large-Scale Environment Using Explainable Neural Networks, Dmitri A. Kalashnikov, Frances V. Davenport, Zachary M. Labe, Paul C. Loikith, John T. Abatzoglou, Deepti Singh

Geography Faculty Publications and Presentations

Lightning is a major source of wildfire ignition in the western United States (WUS). We build and train convolutional neural networks (CNNs) to predict the occurrence of cloud-to-ground (CG) lightning across the WUS during June-September from the spatial patterns of seven large-scale meteorological variables from reanalysis (1995-2022). Individually trained CNN models at each 1° × 1° grid cell ( = 285 CNNs) show high skill at predicting CG lightning days across the WUS (median AUC = 0.8) and perform best in parts of the interior Southwest where summertime CG lightning is most common. Further, interannual correlation between observed and predicted …

Lengthening Atlantic Hurricane Seasons With Earlier Storm Formation Dates Including Implications From 2020, Barry D. Keim, L. C. Hamilton, V. M. Brown, P. J. Klotzbach, A. B. Lewis, D. T. Thompson

School of Public Health Faculty Publications

This paper analyzes the formation dates of the nth storm in a sequence for all named North Atlantic tropical cyclones (TCs) and assesses whether the intraseasonal length of the Atlantic hurricane season has changed temporally. The record-breaking 2020 season, with 30 named storms, set records for the earliest third TC formation (Cristobal) and from the sixth TC (Fay) onward. Analysis of season length from 1851 to 2022 identifies only one statistically significant breakpoint detected in the early 1970s, roughly coinciding with the introduction of satellite observations. Since 1970, we also find a trend toward longer North Atlantic hurricane seasons. The …

Global Empirical Model Of Sporadic-E Occurrence Rates, Eli V. Parsch, Anthony L. Franz, Eugene V. Dao, Dong L. Wu, Nimalan Swarnalingam, Cornelius C. J. H. Salinas, Daniel J. Emmons

Faculty Publications

Intense ionization enhancements in the Earth’s ionosphere, known as sporadic-E (E_s), can degrade and severely disrupt the propagation of radio signals. Although many previous studies have analyzed the characteristics and morphologies of sporadic-E, few efforts have attempted to model global E_s occurrence rates (ORs) at high time resolutions. This study develops a global empirical model of blanketing sporadic-E occurrence rates using a Karhunen–Loéve Expansion (KLE) of a global OR climatology built with Global Navigation Satellite System radio occultation (GNSS-RO) and ionosonde observations. Using an fbE ≥ threshold of 3 MHz, the model outputs a blanketing sporadic-E …