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Full-Text Articles in Meteorology

The Influence Of Complex Coastlines On The Sea Breeze And Convection Initiation In Coastal North Carolina, Logan Howard, Adam L. Houston Mar 2023

The Influence Of Complex Coastlines On The Sea Breeze And Convection Initiation In Coastal North Carolina, Logan Howard, Adam L. Houston

Honors Theses

The sea breeze is a common phenomenon in coastal regions around the world. Their development and propagation can be treated as a density current. It is well known that many factors influence density current propagation, including wind. Depending on the orientation, the wind speed and shear can enhance or inhibit the development of the sea breeze. In places like eastern North Carolina, complex coastal geography can create river and sound breezes that, upon collision, have the potential to initiate thunderstorms. Using Cloud Model 1, simulations were conducted to model the behavior of the sea breezes in eastern North Carolina and …


Climatology Of The Elevated Mixed Layer Over The Contiguous United States And Northern Mexico: 1979–2021, Margo Siciliano Andrews Jan 2023

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 …


A Mesonet-Based Analysis Of Severe Convective Winds In West Texas., Quint Long May 2022

A Mesonet-Based Analysis Of Severe Convective Winds In West Texas., Quint Long

Electronic Theses and Dissertations

Multiple studies have investigated the occurrence of severe convective-related winds and have increased our understanding of the forces driving severe winds and their spatial and temporal patterns. Data for these studies have come from airport stations maintained by the National Weather Service. Their standardization across the United States makes them ideal for research, but they are limited in their distribution. This study aims to create a similar climatology of severe surface level winds using a mesoscale network (“mesonet”). Like their ASOS (Automated Surface Observing System) and AWOS (Automated Weather Observing System) counterparts, these stations are standardized and well maintained. This …


A Temporal Examination Of The Connections Between Convective Available Potential Energy And Convective System Development, Chad A. Small Jan 2022

A Temporal Examination Of The Connections Between Convective Available Potential Energy And Convective System Development, Chad A. Small

Dissertations and Theses

In 1983, the World Climate Research Programme launched its first project: the International Satellite Cloud Climatology Project (ISCCP). While the ISCCP has succeeded in many of its cataloging and analytical goals, one of its flagship products, the Convection Tracking (CT) Database does not contain certain environmental parameters that are essential in understanding how, and when, convection is initiated or intensified. The development of mesoscale convection – notably, convective systems (CS) – is also largely dependent on parameters like convective available potential energy (CAPE) which the ISCCP CT Database does not record. By tying information on CAPE to CS, discoveries in …


A Revised Technique For Measuring Vertical Velocity Using Dropsondes, Timothy Connor Nelson Jan 2019

A Revised Technique For Measuring Vertical Velocity Using Dropsondes, Timothy Connor Nelson

Legacy Theses & Dissertations (2009 - 2024)

The earliest iterations of dropsondes in the 1960's obtained vertical velocity by measuring the geometric fall speed of the dropsonde and the true airspeed (TAS) of the dropsonde from a pitot-static. The vertical velocity errors from this methodology were claimed to be ±1 m s-1. Subsequent dropsonde iterations used various forms of the drag force equation to obtain vertical velocity. The accuracy of these drag force-based measurements, however, are also quite large at ±1–2 m s-1. In this dissertation, an attempt is made to improve vertical velocity errors by revisiting and revising the pitot-static-derived TAS methodology on the eXpendable Digital …


A Diagnostic Examination Of The Eastern Ontario And Western Quebec Wintertime Convection Event Of 28 January 2010, Shawn M. Milrad, John R. Gyakum, Eyad H. Atallah, Jennifer F. Smith Jun 2018

A Diagnostic Examination Of The Eastern Ontario And Western Quebec Wintertime Convection Event Of 28 January 2010, Shawn M. Milrad, John R. Gyakum, Eyad H. Atallah, Jennifer F. Smith

Shawn M. Milrad

The priority of an operational forecast center is to issue watches, warnings, and advisories to notify the public about the inherent risks and dangers of a particular event. Occasionally, events occur that do not meet advisory or warning criteria, but still have a substantial impact on human life and property. Short-lived snow bursts are a prime example of such a phenomenon. While these events are typically characterized by small snow accumulations, they often cause very low visibilities and rapidly deteriorating road conditions, both of which are a major hazard to motorists. On the afternoon of 28 January 2010, two such …


A New Analysis Of The Gálvez-Davison Index For Convective Forecasts In Northern Africa, Gabriel D. Donndelinger Mar 2018

A New Analysis Of The Gálvez-Davison Index For Convective Forecasts In Northern Africa, Gabriel D. Donndelinger

Theses and Dissertations

Severe wind gusts and thunderstorms have been difficult to forecast in Africa. Traditional convective forecast tools (e.g. Total Totals Index, Lifted Index, K Index (KI) and Convective Available Potential Energy) do not accurately portray potential for thunderstorms in Africa. This research effort used the Gálvez-Davison Index (GDI), a convective index created for the tropics, and assess its applicability to northern Africa. GDI was produced for the Caribbean and Central America, and utilized temperature, moisture, mid-level stability, dry air entrainment and an elevation factor to calculate convective potential. In this research, GDI and KI were calculated using Global Forecast System (GFS) …


Tropical Cyclone Rapid Intensification In Environments Of Upper-Tropospheric Troughs : Environmental Influences And Convective Characteristics, Michael Fischer Jan 2018

Tropical Cyclone Rapid Intensification In Environments Of Upper-Tropospheric Troughs : Environmental Influences And Convective Characteristics, Michael Fischer

Legacy Theses & Dissertations (2009 - 2024)

Intensity forecasts for tropical cyclones that undergo a period of rapid intensification are particularly susceptible to large errors. For those storms that interact with an upper-tropospheric trough, tropical cyclone intensity forecasts are complicated, as upper-tropospheric troughs can provide unique intensification mechanisms, but are often associated with unfavorable environmental conditions. Although tropical cyclones in environments with nearby upper-tropospheric troughs are associated with lesser intensification rates than tropical cyclones in environments devoid of upper-tropospheric troughs, some tropical cyclone--trough interactions are associated with a period of rapid intensification. This dissertation utilizes reanalysis output, satellite observations, and ensemble modeling simulations to understand whether rapid …


The Mean And Turbulent Properties Of A Wildfire Convective Plume, Neil Lareau, Craig Clements Aug 2017

The Mean And Turbulent Properties Of A Wildfire Convective Plume, Neil Lareau, Craig Clements

Faculty Publications, Meteorology and Climate Science

The time-mean and time-varying smoke and velocity structure of a wildfire convective plume is examined using a high-resolution scanning Doppler lidar. The mean plume is shown to exhibit the archetypal form of a bent-over plume in a crosswind, matching the well-established Briggs plume-rise equation. The plume cross section is approximately Gaussian and the plume radius increases linearly with height, consistent with plumerise theory. The Briggs plume-rise equation is subsequently inverted to estimate the mean fire-generated sensible heat flux, which is found to be 87 kW m22 . The mean radial velocity structure of the plume indicates flow convergence into the …


Characterization Of Tropical Clouds Using Multi-Satellite Observations, Ricardo Anderson Jan 2015

Characterization Of Tropical Clouds Using Multi-Satellite Observations, Ricardo Anderson

Dissertations and Theses

Clouds an important component of the earth-climate system and play a critical role in affecting energy and water cycle of the planet. In particular, tropical convective clouds account for the majority of the precipitation that fall on the Earth's surface. Multiple active satellite missions in recent decade such as TRMM (Tropical Rainfall Measurement Mission), and CloudSat have provided fruitful new insight into the internal structures of these tropical convective clouds. In conjunction with cloud data from ISCCP (International Satellite Cloud Climatology Project), that is based passive remote sensing technology in the visible and infrared spectrum, this allows for a more …


Comparison And Validation Of Tropical Rainfall Measuring Mission (Trmm) Rainfall Algorithms In Tropical Cyclones, Joseph P. Zagrodnik Nov 2012

Comparison And Validation Of Tropical Rainfall Measuring Mission (Trmm) Rainfall Algorithms In Tropical Cyclones, Joseph P. Zagrodnik

FIU Electronic Theses and Dissertations

Tropical Rainfall Measuring Mission (TRMM) rainfall retrieval algorithms are evaluated in tropical cyclones (TCs). Differences between the Precipitation Radar (PR) and TRMM Microwave Imager (TMI) retrievals are found to be related to the storm region (inner core vs. rainbands) and the convective nature of the precipitation as measured by radar reflectivity and ice scattering signature. In landfalling TCs, the algorithms perform differently depending on whether the rainfall is located over ocean, land, or coastal surfaces. Various statistical techniques are applied to quantify these differences and identify the discrepancies in rainfall detection and intensity. Ground validation is accomplished by comparing the …


Convectively-Coupled Kelvin Waves Over The Tropical Atlantic And African Regions And Their Influence On Atlantic Tropical Cyclogenesis, Michael John Ventrice Jan 2012

Convectively-Coupled Kelvin Waves Over The Tropical Atlantic And African Regions And Their Influence On Atlantic Tropical Cyclogenesis, Michael John Ventrice

Legacy Theses & Dissertations (2009 - 2024)

High-amplitude convectively coupled atmospheric Kelvin waves (CCKWs) are explored over the tropical Atlantic during the boreal summer. Atlantic tropical cyclogenesis is found to be more frequent during the passage of the convectively active phase of the CCKW, and most frequent two days after its passage. CCKWs impact convection within the mean latitude of the inter-tropical convergence zone over the northern tropical Atlantic. In addition to convection, CCKWs also impact the large scale environment that favors Atlantic tropical cyclogenesis (i.e., deep vertical wind shear, moisture, and low-level relative vorticity).


A Diagnostic Examination Of The Eastern Ontario And Western Quebec Wintertime Convection Event Of 28 January 2010, Shawn M. Milrad, John R. Gyakum, Eyad H. Atallah, Jennifer F. Smith Jun 2011

A Diagnostic Examination Of The Eastern Ontario And Western Quebec Wintertime Convection Event Of 28 January 2010, Shawn M. Milrad, John R. Gyakum, Eyad H. Atallah, Jennifer F. Smith

Publications

The priority of an operational forecast center is to issue watches, warnings, and advisories to notify the public about the inherent risks and dangers of a particular event. Occasionally, events occur that do not meet advisory or warning criteria, but still have a substantial impact on human life and property. Short-lived snow bursts are a prime example of such a phenomenon. While these events are typically characterized by small snow accumulations, they often cause very low visibilities and rapidly deteriorating road conditions, both of which are a major hazard to motorists. On the afternoon of 28 January 2010, two such …


Nowcasting Thunderstorms At Cape Canaveral, Florida, Using An Improved Neumann-Pfeffer Thunderstorm Index, Cindy L. Howell Mar 1998

Nowcasting Thunderstorms At Cape Canaveral, Florida, Using An Improved Neumann-Pfeffer Thunderstorm Index, Cindy L. Howell

Theses and Dissertations

The Neumann-Pfeffer Thunderstorm Index (NPTI) is used daily by the 45th Weather Squadron during the convective season to estimate the probability of afternoon thunderstorms. The current I , developed by Charles J. Neumann in the 1960s, i based on only 13 years of data taken over 30 years ago. The index was in desperate need of an upgrade. Following the multiple regression techniques outlined by Neumann, this thesis examines whether or not including additional data would improve the performance of the NPTI. After performing the multiple regressions and retuning the regression coefficients, both NPTs were validated using a 2-year independent …