A Quantitative Look at the Relationship between Enivornmental Vertical Wind Shear and Tropical Cyclone Intesity Change Utilizing Enhanced Satellite Derived Wind Information

The effects of vertical wind shear on a tropical cyclone (TC) structure and intensity change are well known from a qualitative standpoint. However, specific quantitative relationships remain elusive, partly due to the lack of consistent observations of the wind field near TCs over the data sparse oceanic regions TC. The University of Wisconsin Cooperative Institute for Meteorological Satellite Studies (UW-CIMSS) program to develop high density wind observations from multispectral geostationary satellite imagery provides added information on vertical wind structure in the TC environment. CIMSS currently produces gridded a wind shear analysis which include the assimilation of the satellite- derived winds. This 3-year archive of high-resolution analyses is used to determine quantitative thresholds of shear and time derivatives of shear versus intensity as a function of TC size, strength, and potential intensity. These analyses will also be used to examine differences in wind shear roles in the two Northern Pacific basins, as well as the Northern Atlantic basin.