Accession Number : ADA327176

Title :   The Outer Radius Tangential Winds of Tropical Cyclones.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Cocks, Stephen B.

PDF Url : ADA327176

Report Date : 10 JUL 1997

Pagination or Media Count : 116

Abstract : Knowledge of the strength and horizontal extent of damaging winds from the center of a tropical cyclone is crucial for coastline preparations, forecasting coastal flooding and shipping interests. This study attempts to improve our understanding, estimation and prediction of the outer wind profiles of typhoons. The mean radii of 30 knot (R30), 50 knot (R50) and 65 knot (R65) winds are calculated using aircraft reconnaissance, satellite and synoptic data for 35 tropical cyclones during approximately 300 different time periods. By examining the change in the outer wind profile with time and central pressure, three cyclone classes were noted. One class of cyclones experiences a R30 increase which persists at least one day past its maximum intensity; these are termed 'delayed.' Another class experiences a trend in R30 that follows the trend in the central pressure; these are termed as 'simultaneous'. Similar differences were noted for R50 and R65 in simultaneous and delayed cyclones. However, the differences in the two cyclone classes diminish as one goes closer to the inner core. A less common class of cyclone had R30 values that were very large from the beginning of their formation and remained large throughout most of its life cycle. These were designated 'gyre' cyclones. Changes in outer winds as related to time of year, cyclone direction of motion, cyclone size and intensity are discussed for these cyclone classes. Composites of each cyclone class were created and the life cycle of the outer winds, central pressure, eye size, and synoptic size were investigated.

Descriptors :   *TROPICAL CYCLONES, *TYPHOONS, AERIAL RECONNAISSANCE, DAMAGE, WIND, THESES, WEATHER FORECASTING, SURFACE PROPERTIES, ERROR ANALYSIS, ARTIFICIAL SATELLITES, PRESSURE, LIFE CYCLES, LINEAR REGRESSION ANALYSIS, FLOODING, RADIUS(MEASURE), SYNOPTIC METEOROLOGY.

Subject Categories : Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE