92nd American Meteorological Society Annual Meeting (January 22-26, 2012)

Thursday, 26 January 2012: 11:30 AM
Composite Maps of East Coast Bomb and Ordinary Cyclogenesis and Associated Quasigeostrophic Analyses
Room 238 (New Orleans Convention Center )
Evan Thomas, Mississippi State University, Mississippi State, MS; and A. E. Mercer

Numerous studies have found that East Coast cyclogenesis is primarily affected by quasigeostrophic (QG) forcing mechanisms, such as vorticity and warm air advection. However, no study has used principal component analysis to diagnose the primary QG controls on East Coast bomb and ordinary cyclogenesis. Previous composite studies of East Coast cyclogenesis have focused primarily on averaging, often damping important atmospheric characteristics relevant to distinguishing different deepening rates. As such, a principal component analysis is used to create composite maps of base-state meteorological variables of ordinary and bomb cyclones (i.e. temperature, moisture, geopotential height, and u and v wind). These composites allow for diagnosis of the common QG diagnostics and synoptic setups of bomb and ordinary cyclogenesis, possibly serving as an aid for forecasters in distinguishing the differences in these deepening rates with some skill. The composite fields will be used to determine relevant QG and synoptic-scale mechanisms that distinguish between the cyclone types. The resulting variables will be compared using permutation testing to ensure statistical significance of the results. Variables which are shown to be statistically significantly different between ordinary and bomb cyclones will be retained from the composites to identify the physical nature of the differences between the cyclone types.

Supplementary URL: