Summary: | A basic climatology of tropical cyclogenesis and pre-genesis evolution is presented using Dvorak classifications of tropical systems. In the absence of adequate in situ observations, the Dvorak technique provides a standardized method for making subjective intensity estimates of tropical systems, based upon a system's organization and structure depicted on satellite imagery. Although the Dvorak technique analysis is performed for all tropical disturbances the forecaster deems to have potential for further development, not every system thus analyzed develops further. A repository of Dvorak data allows a comparison of incipient systems to determine statistical characteristics of genesis in tropical systems. A standardized formatted database of Dvorak analyses for all disturbances in the east and central North Pacific as well as North Atlantic tropical basins from 2001-2008 is constructed using fixes from the Central Pacific Hurricane Center (CPHC) and the National Hurricane Center (NHC). The addition of best track data from the CPHC, the NHC, and the Joint Typhoon Warning Center (JTWC) provides statistical probabilities of tropical cyclogenesis based on historical relationships of Dvorak classification. For example, incipient disturbances with a Dvorak Current Intensity (CI) classification of 1.0 develop within 48 hours about 35% of the time in the Atlantic basin, 50% of the time in East Pacific (east of 125À W), and 15% of the time in the Central Pacific (west of 125À W to 180À). These statistics may also provide a baseline for operational probabilistic genesis guidance and for future, more advanced genesis prediction techniques. Advisor: Dr. Robert Hart, Florida State University, College of Arts and Sciences, Dept. of Meteorology. Thesis (Honors paper)--Florida State University, 2010. Includes bibliographical references.
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