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Full-Text Articles in Physical Sciences and Mathematics
An Overview And Evaluation Of Synthetc: A Statistical Model For Extra-Tropical Cyclones, Rafael Uryayev
An Overview And Evaluation Of Synthetc: A Statistical Model For Extra-Tropical Cyclones, Rafael Uryayev
Dissertations and Theses
Extratropical cyclones (ETCs) are the most common weather phenomena affecting the United States, Canada, and Europe. They can pose serious hazards over large swaths of area. In this thesis, a statistical model of ETCs, called SynthETC, is discussed. The model accounts for the for genesis, track path, termination, and intensity of statistically generated ETCs. Genesis is modeled as a Poisson process, whose mean is determined by climate and historical information. Tracks are modeled as a regression-mean determined by climate and historical information plus a stochastic component. Lysis is modeled using logistic regression, with climate states as covariates. Intensity is modeled …
Synergistic Effects Of Midlevel Dry Air And Vertical Wind Shear On Tropical Cyclone Development, Joshua James Alland
Synergistic Effects Of Midlevel Dry Air And Vertical Wind Shear On Tropical Cyclone Development, Joshua James Alland
Legacy Theses & Dissertations (2009 - 2024)
This dissertation seeks to better understand how midlevel moisture and vertical wind shear (VWS) modulate tropical cyclone (TC) development. The first component of this dissertation simplifies the objective by focusing solely on how midlevel moisture modulates TC development, utilizing an axisymmetric modeling framework. Results show that low-entropy midlevel air affects the upward vertical mass flux in these experiments through subsidence into the subcloud layer, which results in a longer recovery time before deep convection develops. This process, as well as descending motion closer to the inner core, limits the radial width of deep convection, reduces the area of upward motions, …
Applying Forecast Track And Intensity Diagnostics To High-Impact Northeast Winter Storms, Tomer Burg
Applying Forecast Track And Intensity Diagnostics To High-Impact Northeast Winter Storms, Tomer Burg
Legacy Theses & Dissertations (2009 - 2024)
A conventional forecasting notion is that as lead time decreases, numerical weather prediction models exhibit a leftward (i.e., west) trend in the forecast position of low-pressure systems along the East Coast of the U.S. This left trend, which may turn seemingly weak ocean cyclones into high-impact weather events for the Northeast U.S., is attributed to various potential causes, such as variability in upstream shortwave troughs, or the representation of latent heat release in the NWP models downstream of the trough associated with the incipient cyclone. This study seeks to address whether this rule of thumb holds any significant merit, and …
On The Frequency, Structure, And Characteristics Of Tropical Cyclone Diurnal Pulses, Sarah Dunn Ditchek
On The Frequency, Structure, And Characteristics Of Tropical Cyclone Diurnal Pulses, Sarah Dunn Ditchek
Legacy Theses & Dissertations (2009 - 2024)
Taking 6-h IR brightness temperature differences, Dunion et al. (2014) found that in major hurricanes, an area of cold cloud tops routinely propagated radially outward from the storm core at around 5–10 m/s over the course of each day. They defined this feature as a “diurnal pulse” and created a 24-h conceptual clock that identified at which radius the coldest cloud tops would be located based on local time (LT). Due to the inherent predictability of these pulses, this dissertation was undertaken to gain a deeper understanding of their frequency, structure, and characteristics.
Extratropical Precursors To The Onset Of Madden-Julian Oscillation Deep Convection Over The Western Indian Ocean, Jennifer Anne Gahtan
Extratropical Precursors To The Onset Of Madden-Julian Oscillation Deep Convection Over The Western Indian Ocean, Jennifer Anne Gahtan
Legacy Theses & Dissertations (2009 - 2024)
Madden-Julian Oscillation (MJO) deep convection often initially forms over the western Indian Ocean and is frequently preceded by upper tropospheric circulation precursors. These precursors include subtropical cyclonic Rossby gyres near eastern Africa and Southwest Asia, coherent extratropically circumnavigating Rossby wave trains extending back across the Atlantic, and tropically circumnavigating easterlies. Easterly acceleration associated with the circulation precursors may help to reduce large-scale subsidence over the tropical Indian Ocean prior to convective onset; when intraseasonal easterly acceleration reaches the western extent of a region of intraseasonal upper level westerlies, it produces upper-tropospheric divergence, providing a forcing for upward motion.
The Role Of The Subtropical Jet In Severe Dry Season Caribbean Rainstorms, Marshall D. Pfahler
The Role Of The Subtropical Jet In Severe Dry Season Caribbean Rainstorms, Marshall D. Pfahler
Legacy Theses & Dissertations (2009 - 2024)
The Caribbean region experiences a bimodal climate with a dry season during November/December–May/June and a wet season encompassing the remainder of the year. Although significant high-impact heavy rainfall events in the Caribbean are typically associated with tropical cyclones (TCs) during the wet season, significant heavy rainfall events can also occur during the Caribbean dry season without contributions from TCs. Dry season Caribbean rainstorms (CRs) can produce infrastructure- and life-threatening conditions through flooding, mudslides, and damaging winds. The most severe dry season CRs can require international aid for vital recovery resources. Severe dry season CRs can produce rainfall totals that substantially …
Influence Of Upper-Tropospheric Troughs On Tropical Cyclone Intensity Change And Structure : Observational, Reanalysis, And Idealized Numerical Modeling Perspectives, Casey Peirano
Legacy Theses & Dissertations (2009 - 2024)
The interaction between tropical cyclones (TCs) and upper-tropospheric troughs is a