Atmospheric Sciences Commons^™

Identifying Saharan Air Layer Events And Their Relationship To Instability And Rainfall Patterns In The Tropical North Atlantic Ocean, Charles H. Dolce

LSU Master's Theses

Every year, strong North African winds across the Sahara loft dust particles and advect them westward within the Saharan Air Layer (SAL). These plumes of dust often reach the Caribbean Sea and can heavily affect regional weather patterns by suppressing convection. When concentrations are high, decreased rainfall can yield negative societal and ecological impacts, potentially leading to drought. The Puerto Rican early rainfall season (ERS), spanning from 1 April through 31 July, overlaps with Saharan dust migration periods, and systematically detecting instances of SAL activity near the island is important for understanding longer-term drought-forcing trends in the region.

Corridors of …

Characterizing Rainfall Variability Within A Series Of Storms Over Northern California In February 2017, Parker Jan Malek

Dissertations and Theses

In February 2017, a series of storms with associated atmospheric rivers (ARs) made landfall in the US state of California, dropping large amounts of precipitation over the Sierra Nevada Mountains and their western foothills. The rainfall from these ARs, long, narrow bands of water vapor that transport large amounts of water vapor from the tropics to the mid-latitudes, instigated the near-failure of the Oroville Dam located at the southeastern edge of the Feather watershed outside the city of Oroville in the state's Central Valley. This case study provides a synoptic and mesoscale diagnosis of the drivers of rainfall pulses that …

Urban Heat Dynamics In Pune: The Influence Of Land Cover And Local Climate, Arpit Tiwari, Preethi Nanjundan, Ravi Ranjan Kumar, Ananya Karmakar, Satyaban Bishoyi Ratna

Northeast Journal of Complex Systems (NEJCS)

Urban areas with high population density and extensive infrastructure development have been experiencing an increasing strain on the local heat budget, leading to a surge in heat-related illnesses and discomfort. This study examined the impact of climate and land use as heat islands in Pune, India, from 2012 to 2023 at six different locations representing varying degree of urbanization. Satellite land cover observations revealed that 55.17% of the total area was urbanized in the city itself, which was limited to 44.8% in 2012. This urbanization has significantly impacted the increasing tendency of maximum temperature (T_max; 0.13℃ to 1.63℃ …

2024 Nhc Verification Report Preview: Atlantic Basin, John Cangialosi, Jon Martinez

National Oceanographic and Atmospheric Administration: Technical Reports and Related Materials

The National Hurricane Center (NHC) is nearing completion of the post-analysis of the 2024 Atlantic and eastern North Pacific basin tropical cyclones. The annual NHC Verification Report uses the post-analyzed information to verify the accuracy and biases of NHC forecasts and real-time model guidance, and the 2024 report will be available in the spring on NHC’s website - https://www.nhc.noaa.gov/verification/. This short review provides some of the preliminary highlights of NHC’s 2024 forecast performance in the Atlantic basin, which is based on a combination of post-analyzed and real time best track data. If interested in the forecast verification for individual …

The Unique Features Of Typhoon Rai (2021): An Observational Study, Clint Eldrick R. Petilla, Lyndon Mark P. Olaguera, Faye Abigail T. Cruz, Jose Ramon T. Villarin, Hironori Fudeyasu, Ryuji Yoshida, Jun Matsumoto

Physics Faculty Publications

Tropical Cyclone (TC) RAI (2021) made a devastating landfall in the Siargao-Dinagat Islands of the southeastern Philippines on December 16, 2021, causing about USD 942 M in damage, 405 reported deaths and 52 missing. Yet, observational studies on the environmental conditions during TC RAI remain limited, and a comparison with other landfalling TCs were not done. To shed light on the factors that made this TC reach a maximum sustained wind speed (MSW) of 105 kts (194.5 kph) and 915 hPa mean sea level pressure according to the WMO-IBTrACS, this study investigated the meteorological statistics of this TC relative to …

Rain-On-Snow Event Climatology And Hydrological Impacts In The Connecticut River Watershed, Samuel Davidson

Masters Theses & Specialist Projects

Rain-on-snow events, characterized by rain falling on existing snowpack, have the potential to bring about significant hydrological and environmental impacts including snowmelt, flooding, landslides, and other natural hazards. Despite prior evidence suggesting the Connecticut River Watershed has endured socioeconomic and environmental setbacks due to rain-on-snow events in the past, limited prior research has been performed on the role of rain-onsnow events within the region’s hydroclimatology. Gaining a deeper understanding of the occurrence and impacts of such events would provide valuable insights for risk and water resource managers. The purpose of this research was to create a climatology of rain-on-snow events …

Statistical Analysis Of Climate Trends And Variability In Tarrant County Using Annual, Decade, And Three-Decade Time Periods, Quinnton Debolt

Earth & Environmental Sciences Theses - Archive

This study is a statistical analysis of climate trends within the Dallas-Fort Worth metroplex according to several time-scale models to understand how the climate for the locality has changed and to provide a basis for projections of what future climate might look like. Trends in mean temperature and precipitation for North Central Texas generally correlate with corresponding global trends linked to natural variability and anthropogenic-induced climate change. Temperature rises in this region annually by 0.08°C and by 0.22°C for a three-decade average. Seasonal increases in three-decadal averages of temperature for North Central Texas relative to the average of the reference …

Stratospheric Variability And Its Relationship To Cold Air Outbreaks In The United States, Paul T. Panhans

Electronic Theses & Dissertations (2024 - present)

Only since the early 2000s, has there been a growing body of work linking extreme winter temperature anomalies to the variability of the Northern Hemisphere stratospheric polar vortex (SPV). However, the understanding behind stratosphere-troposphere coupling and cold air outbreaks (CAOs) remain occasionally contradictory in the literature, making it difficult to properly articulate societal risks. Studies often focused on broad stratospheric influences, but this research directly compared stratospheric variability according to their respective tropospheric impacts. This dissertation filled a knowledge gap, as there has yet to be a comprehensive analysis to quantify the differences in stratospheric variability with and without CAOs …

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 …

High-Altitude Balloon-Launched Uncrewed Aircraft System Measurements Of Atmospheric Turbulence And Qualitative Comparison With Infrasound Microphone Response, Anisa Haghighi

Theses and Dissertations--Mechanical and Aerospace Engineering

This study explores the use of a balloon-launched uncrewed aircraft system (UAS) to measure atmospheric turbulence in the troposphere and lower stratosphere using both wind velocity measurements and infrasonic acoustic energy. The UAS, a glider configured for autonomous descent along a predefined trajectory, had on board, in situ sensors to capture thermodynamic and kinematic atmospheric parameters. Additionally, it carried an infrasonic microphone to evaluate its potential for remotely detecting clear-air turbulence by capturing infrasonic waves. The system’s performance was assessed over the course of three test flights conducted in New Mexico, USA, in 2021. The descent enabled high-resolution profiling, with …

A Wall Of Smoke: Understanding The Drivers Of The June 2023 Canadian Wildfire Smoke Event For New York City, Gregory S. Randazzo

Dissertations and Theses

The 2023 Canadian wildfire season was notable for its extent and the dense smoke it produced. Motivated by the resulting air quality impacts in the New York City region, we explore how the total particulate matter output from the Quebec fires influenced PM2.5 concentrations downstream in New York City. Using injection height data from the Regional Advanced Baseline Imager + VIIRS Emissions dataset, we relate the tropospheric injection heights of the fires with the broader synoptic context and surface PM2.5 concentrations. Using data from the NYS Mesonet Profiler Network, radiosondes, and ERA5 reanalysis, we document the connection between an anomalous …

Limitations Of The High-Resolution Rapid Refresh Gust Algorithm, Alex M. Glasser

Electronic Theses & Dissertations (2024 - present)

ABSTRACT:

Accurate wind and gust forecasts are crucial in operational meteorology, yet there is a distinct gap in the literature regarding the verification of operational gust forecasts. In the present work, we assess the performance of the High-Resolution Rapid Refresh's (HRRR) gust potential, verifying it against the Automated Surface Observing System's (ASOS) observed gusts across the Continental United States (CONUS). The HRRR gust's diurnal cycle reveals a significant underprediction of the gust during daylight hours and a slight overprediction of the gust during hours of darkness. The daytime underprediction undermines the assumption that forecasts represent a potential that tends to …

Using The High Resolution Rapid Refresh To Validate A Novel Forecast Methodology, Sylvia M. Garmong

Electronic Theses & Dissertations (2024 - present)

NOAA’s High-Resolution Rapid Refresh (HRRR) is frequently used by forecasters for short term predictions and although the model performs well in many metrics, previous study (Fovell and Gallagher 2020) identified temperature and windspeed biases within the boundary layer using radiosonde and surface observations. The current work uses a forecast drift metric to study how model forecasts evolve with time and distance to radiosonde sites. The metric is calculated by subtracting model analysis from forecasts at the same valid time, creating a proxy for bias. HRRR data on native model levels are obtained from the Google Cloud and Amazon Web Services …

Convective Modes Associated With Precipitation Exceeding Postfire Debris Flow Thresholds In The Southwestern United States, Anya M. Aponte Torres

Graduate Research Theses & Dissertations

Postfire debris flows can occur when surface-water runoff dislodges and carries a slurry of loose sediment and vegetation downslope, usually in steep, recently burned terrain. Short-duration, high-intensity rainfall embedded within short or long-duration rainstorms (e.g., thunderstorms and atmospheric rivers) is most commonly associated with this mode of debris-flow initiation. The typical horizontal grid spacings of global numerical weather prediction and general circulation models are too coarse to resolve these convective precipitation features, which poses an obstacle to short-term forecasting and investigating future trends in the frequency, magnitude, and characteristics of debris-flow generating rainfall. For this study, 15-minute precipitation and simulated …

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 …

Understanding The Dynamical Mechanisms Governing Northern Hemisphere Wintertime Persistent Flow Regimes And Their Associated Extreme Weather Events, Tyler Christopher Leicht

Electronic Theses & Dissertations (2024 - present)

Weather regimes are characterized as patterns of low-frequency variability in the middle to upper troposphere of the extratropics. Weather regimes can also be linked to variations in surface weather, making the study of weather regimes a bridge between traditional synoptic-dynamic meteorology and subseasonal-to-seasonal variability. This dissertation identifies and categorizes persistent flow regimes (PFRs), analyzes the dynamics underpinning PFR formation, identifies the linkages to atmospheric teleconnections, and examines the occurrence of surface weather extremes before and during PFRs.

PFRs are identified from 1979–2022 and grouped into five clusters using k-means clustering, which then allows for time-lag composite analysis to determine 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.

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

Funded Research Records

No abstract provided.

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, …

Typology Of Atmospheric Conditions Leading To Dam Overtopping In The Eastern Us, Hodo I. Orok, Deanna Hence

I-GUIDE Forum

Statistical characterization of reanalysis datasets during over 300 hydrologic dam incidents between 2003 and 2022 will create a detailed typology of weather systems associated with dam overtopping in the eastern United States. Dam overtopping poses significant risks to infrastructure and public safety, necessitating a comprehensive understanding of the multi-scale atmospheric conditions that lead to such events. To better account for the natural flow of water to the affected dams, we will adopt a watershed-focused Principal Component Analysis (PCA) on regional atmospheric data collected from ERA5 alongside USGS streamflow and Stage IV precipitation observations to enhance understanding of high-risk weather conditions. …

Creating Sustainable School And Home Gardens: Using Weather Stations, Jake Sanders, Daniel Findlay, Kathy Cabe Trundle, Rita Hagevik, Kaitlin Campbell

All Current Publications

This fact sheet provides an overview of how weather stations work and the steps to set up your own weather station. To help monitor the water conditions, wind speeds, and temperatures that can impact your plants, we suggest adding a weather station to your garden area or greenhouse.

Managing Frost Risk, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Frost occurs on clear nights in early spring when the air temperature drops to 2°C or less. Crop damage from frost may occur at any stage of development but is most damaging at or around flowering.

Frost is difficult to manage, and damage will be unavoidable in some seasons. Risk management options proven to reduce frost risk include paddock zoning, crop and variety selection, time of sowing, stubble management and managing inputs. The greatest gains result from in paddock choice/zoning, crop and variety choice, and manipulating the canopy.

Coastal Sedimentary Records Of Extreme Events And Human Activity: Examples From Hurricanes And Microplastics, Nicholas T. Culligan

LSU Doctoral Dissertations

Coastal regions are uniquely vulnerable to a myriad of natural and anthropogenically caused stresses such as hurricane strikes and chronic microplastic pollution. Both hurricanes and microplastics have major negative effects on global coastlines and are forecast to become more damaging in the future. However, current model trends are based on limited modern data and may not provide an accurate or comprehensive view of the future. Therefore, this dissertation investigates coastal stratigraphic records to determine long-term past trends of these presses and pulses so that researchers, stakeholders, and policy makers can use them to enact strategies to mitigate damages from worsening …

Sensitivity Of Present And Future Seasonal Precipitation Over Central United States To The Representation Of Rocky Mountain Topography, Ranasinghe Disanayakalage Sherly Shelton Ranathunga

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Precipitation change across the Central United States (USA) is of great interest to the research community. Studies using global climate simulations suggest that the “100^th-Meridian”, which separates the “dry west” from the “moist east” will shift to the east as the climate responds to future emissions pathways. However, these simulations are run at relatively coarse resolutions, which do not accurately represent topography. Here, we perform regional simulations using the Weather Research and Forecasting (WRF) model to explore the sensitivity of present and future precipitation patterns across the central USA to the representation of the Rocky Mountains (RM). We …

Balloon Borne Gps-Enabled Radiosondes That Enable Simultaneous Multi-Point Atmospheric Sensing With A Single Ground Station, Peter A. Ribbens

Doctoral Dissertations and Master's Theses

Radiosondes are balloon borne atmospheric instruments that are a critical tool for understanding dynamics in the lower layers of the atmosphere. The low-cost radiosondes developed in the Space and Atmospheric Instrumentation Lab have been further developed to improve the system's use as a science-quality atmospheric instrument that is unique in its ability to simultaneously track multiple sondes with a single ground station. Sensors to measure temperature and pressure were added to improve measurements of the atmospheric state. A printed circuit board shield and 3D-printed shell were designed to make mass manufacturing possible. A thermistor-based temperature sensor was developed and tested …

Toward Untangling Thunderstorm-Aerosol Relationships: An Observational Study Of Regions Centered On Washington, Dc And Kansas City, Mo, Mace Bentley, Tobias Gerken, Zhoujun Duan, Dudley Bonsal, Henry Way, Endre Szakal, Mia Pham, Hunter Donaldson, Lucie Griffith

School of Integrated Sciences - Faculty Scholarship

A multi-variable investigation of thunderstorm environments in two distinct geographic regions is conducted to assess the aerosol and thermodynamic environments surrounding thunderstorm initiation. 12-years of cloud-to-ground (CG) lightning flash data are used to reconstruct thunderstorms occurring in a 225 km radius centered on the Washington, D·C. and Kansas City Metropolitan Regions. A total of 196,836 and 310,209 thunderstorms were identified for Washington, D.C. and Kansas City, MO, respectively. Hourly meteorological and aerosol data were then merged with the thunderstorm event database.

Evidence suggests, warm season thunderstorm environments in benign synoptic conditions are considerably different in thermodynamics, aerosol properties, and aerosol …

Multi-Case Study Of Left-Flank Boundaries Within Supercells, Peyton B. Stevenson

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

This study investigates the prevalence and significance of forward-flank convergence boundaries (FFCBs) and left-flank convergence boundaries (LFCBs) in shaping the structure and intensity of supercells, using observational data from various field projects. Unlike previous research focusing on individual cases, this study examines a diverse range of cases to provide comprehensive insights into the relationship between these boundaries and supercell characteristics such as intensity, longevity, and tornadogenesis. By analyzing high-resolution surface data, the research addresses the frequency, location, and intensity of these boundaries, and their impact on pseudo vertical vorticity, pseudo convergence, and density gradients. A total of 228 boundary identifications …

Design And Evaluation Of An Esa-Based Method Of Ensemble Subsetting For A Wofs (Warn On Forecast-Like System), Daniel J. Butler

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Forecasting severe thunderstorm environments in the southeastern United States can be challenging due to mesoscale heterogeneities such as shortwave troughs, pre-existing airmass boundaries, cold fronts aloft, low-level jets, dry air intrusions, and mesoscale lows. To combat these challenges, ensemble sensitivity analysis (ESA) may be applied to a Warn-on-Forecast (WOF)-like ensemble to improve forecasts of severe convection through ensemble weighting and subsetting. Ensemble-based weighting and subsetting uses ensemble members that most accurately represent the thunderstorm environment in areas of mesoscale heterogeneity. This study creates and evaluates the ensemble-based weighting and subsetting in four cases of severe thunderstorm occurrence. The open parameter …