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Full-Text Articles in Meteorology

The Upper-Level Turbulence, Static Stability And Tropopause Structure Of Tropical Cyclones, Patrick Duran Jan 2018

The Upper-Level Turbulence, Static Stability And Tropopause Structure Of Tropical Cyclones, Patrick Duran

Legacy Theses & Dissertations (2009 - 2024)

Upper-tropospheric thermodynamic processes can play an important role in tropical cyclone (TC) structure and evolution. Despite its importance, until recently few in-situ observations were available in the upper levels of TCs. Two recent field campaigns -- the National Aeronautics and Space Administration (NASA) Hurricane and Severe Storm Sentinel (HS3) and the Office of Naval Research Tropical Cyclone Intensity (TCI) experiment -- provided a wealth of high-altitude observations within TCs. These observations revealed that the upper-level static stability and tropopause structure of TCs can change dramatically with both space and time.


Predictability Of African Easterly Waves In An Operational Ensemble Prediction System, Travis J. Elless Jan 2018

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 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 …