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Full-Text Articles in Meteorology

Analysis Of Intraseasonal Convective Variability Modes Over West Africa During The Monsoon Season, Jeffrey Ceratto Jan 2012

Analysis Of Intraseasonal Convective Variability Modes Over West Africa During The Monsoon Season, Jeffrey Ceratto

Legacy Theses & Dissertations (2009 - 2024)

Intraseasonal variability of rainfall within the West African Monsoon has been shown to be an important factor in the weather of this region. Multiple factors have been found to contribute to variability at this timescale. Mounier, et al (2008) use EOF analysis to uncover and describe a quasi-stationary dipole of precipitation between the West African Monsoon system and the West Atlantic/Caribbean Sea. This mode, termed the Quasi Biweekly Zonal Dipole mode, operates on timescales of roughly 13 days. The stationary nature of this dipole is focused upon in their work, while the role of Kelvin waves in the mode are …


An Analysis Of The Formation And Evolution Of The 1989 Western North Pacific Subtropical Gyre, Brian Andrew Crandall Jan 2012

An Analysis Of The Formation And Evolution Of The 1989 Western North Pacific Subtropical Gyre, Brian Andrew Crandall

Legacy Theses & Dissertations (2009 - 2024)

This thesis conducts an observational study of a large cyclonic gyre that developed in the Western North Pacific (WNP) in late July 1989. For a period of six days, azimuthally-averaged winds at 850 hPa remained cyclonic out from the center of circulation to the 2000 km radius, with azimuthally-averaged tangential wind speeds at or greater than 10 m s-1. The gyre exhibited an asymmetric convection pattern, with the center, north and west flanks devoid of large convective areas, but the southern and eastern flanks maintained large-scale convective regions, extending as much as 4000 km in longitude.


A Wrf Simulation Of The Asymmetric Rapid Intensification And Trough Interaction Of Tropical Storm Gabrielle (2001), Diana Elizabeth Thomas-Abernethy Jan 2012

A Wrf Simulation Of The Asymmetric Rapid Intensification And Trough Interaction Of Tropical Storm Gabrielle (2001), Diana Elizabeth Thomas-Abernethy

Legacy Theses & Dissertations (2009 - 2024)

Despite 13 ms-1 ambient wind shear, Tropical Storm (TS) Gabrielle underwent 22 hPa pressure falls within 3 hours prior to 0900 UTC 14 September. The rapid intensification of Gabrielle was atypical due to an upper-level trough approaching from the northwest. Additionally, a convective cell developed in the downshear left quadrant of the center, moved cyclonically and inward to the 17 km radius. During this time, The Tropical Rainfall Measurement Mission (TRMM) had one of its most intense 85 GHz scattering measurements ever (Molinari and Vollaro, 2010).


Appalachian Lee Troughs And Their Association With Severe Convective Storms, Daniel Thompson Jan 2012

Appalachian Lee Troughs And Their Association With Severe Convective Storms, Daniel Thompson

Legacy Theses & Dissertations (2009 - 2024)

Forecasting convective storms in the mid-Atlantic region of the U.S. (hereafter mid-Atlantic) is important because of the proximity of the convective initiation region to major East Coast cities. These forecasts can be challenging because of the weak synoptic-scale forcing for ascent and abundant convective instability typical of the mid-Atlantic warm season (May-September). As a result, mesoscale boundaries such as the Appalachian lee trough (ALT) play an important role in initiating convective storms. This thesis examines the association between ALTs and warm-season severe convective storms in the mid-Atlantic in order to understand how ALTs modulate the frequency and distribution of severe …


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).


The Influence Of The Great Lakes On Mcs Formation And Development In The Warm Season, Alan Frederick Srock Jan 2011

The Influence Of The Great Lakes On Mcs Formation And Development In The Warm Season, Alan Frederick Srock

Legacy Theses & Dissertations (2009 - 2024)

This study focuses on how near-surface thermal boundaries that form near the Great Lakes during the warm season can contribute to the formation of mesoscale convective systems (MCSs). Differential heating across land-water interfaces can create a cold dome of air over the lake; convection may develop when the relatively-cold dome of air becomes deep enough to enable air parcels that intersect these boundaries to reach their level of free convection. A radar-based climatology of MCS events surrounding the Great Lakes for 2002-2005 showed that MCSs frequently form in the vicinity of the Great Lakes. Composites of MCS events over the …


The Investigation Of Snowfall Rate Using Optical Techniques, Gerald J. Mulvey Jan 1973

The Investigation Of Snowfall Rate Using Optical Techniques, Gerald J. Mulvey

Atmospheric and Environmental Sciences Theses and Dissertations

Experiments involving the attenuation of light by falling snow, or hydrometeors in general, lend themselves to the study of at least two problems of meteorological interest. The first problem is that of visibility in adverse weather conditions, and the second is that of finding a better method to measure precipitation. From the late 1940's through the late 1960's, various investigators have attempted to apply forward light scattering theory in the geometric optics range (α ≥ 200, where α = (2π_r)/λ, λ=wavelength and r = radius)* to quantitatively describe the attenuation of a light beam, and thereby visibility changes due to …