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Full-Text Articles in Meteorology
Comparison Of 2018-2021 Tropical Cyclone Track Forecasts Before And After Noaa G-Iv Missions, Melissa Piper
Comparison Of 2018-2021 Tropical Cyclone Track Forecasts Before And After Noaa G-Iv Missions, Melissa Piper
Legacy Theses & Dissertations (2009 - 2024)
Tropical cyclone (TC) hazards are primarily dictated by the TC position; thus, it is important to produce accurate TC track forecasts. Many different features can influence a TC’s motion, yet these features are not always well sampled by in-situ observations over the open ocean, creating a need for supplemental observation collected via aircraft, including the deployment of dropsondes. In 1997, the National Hurricane Center (NHC) began operational synoptic surveillance missions in the near-storm environments of TCs using the Gulfstream IV-SP jet aircraft (G-IV), with the goal of reducing track forecast errors. In the first 10 years of operational missions, the …
A Comparison Of The Upscale Influence Of Various Planetary Boundary Layer Turbulence Parameterizations On The Evolution Of Extratropical Cyclones, Matthew Vaughan
A Comparison Of The Upscale Influence Of Various Planetary Boundary Layer Turbulence Parameterizations On The Evolution Of Extratropical Cyclones, Matthew Vaughan
Legacy Theses & Dissertations (2009 - 2024)
Subgrid-scale turbulence in numerical weather prediction models is typically handled by a PBL parameterization. These schemes attempt to represent turbulent mixing processes occurring below the resolvable scale of the model grid in the vertical direction, and they act upon temperature, moisture, and momentum within the boundary layer. This dissertation utilizes idealized and full-physics numerical model simulations to understand how variations in turbulent mixing parameterizations may influence sensible weather forecasts of baroclinic cyclones across a variety of spatial and temporal scales. Furthermore, a primary pathway through which PBL turbulence projects upscale during baroclinic cyclone events is identified using a combination of …
Predictability Of African Easterly Waves In An Operational Ensemble Prediction System, Travis J. Elless
Predictability Of African Easterly Waves In An Operational Ensemble Prediction System, Travis J. Elless
Legacy Theses & Dissertations (2009 - 2024)
African easterly waves (AEWs) are the primary synoptic-scale weather feature found in sub-Saharan Africa during boreal summer. Many studies have used observations and idealized models to highlight processes associated with the movement and growth of AEWs, yet there have been few studies documenting the performance of operational ensemble prediction systems (EPSs) for these phenomena. Here, the predictability of AEWs in ECMWF EPS forecasts is assessed during two periods of enhanced AEW activity (July--September 2007--2009 and 2011--2013). Specifically, AEW predictability is analyzed through three main areas of focus: 1) verifying AEW position and intensity forecasts, and assessing their relation to convective …
Tropical Cyclone Rapid Intensification In Environments Of Upper-Tropospheric Troughs : Environmental Influences And Convective Characteristics, Michael Fischer
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 …
Evaluating Preferred Direction Tropical Cyclone Track Variability In An Operational Global Ensemble Prediction System, Travis Elless
Evaluating Preferred Direction Tropical Cyclone Track Variability In An Operational Global Ensemble Prediction System, Travis Elless
Legacy Theses & Dissertations (2009 - 2024)
Ensemble forecasts of Tropical Storm Debby and Hurricane Sandy (2012) highlight instances where variability in tropical cyclone (TC) position forecasts are stretched along a preferred direction. The goal of this thesis is to analyze this stretching of variability in a global ensemble prediction system, particularly the European Centre for Medium-Range Weather Forecasts (ECMWF), to determine how often and under what conditions does variability stretching occur, and ultimately what feature(s) are responsible for generating this variability.