Evaluations of Actual and Adjusted Wind–Pressure Relationship of Tropical Cyclone Using Aircraft-Assisted Best Track Data

Abstract

The relationship between maximum sustained wind speed (V_max) and minimum sea level pressure (P_min) of tropical cyclones (TC), which is called the wind–pressure relationship (WPR), is investigated by using best track data in which aircraft observations are used. On average, for given V_max (P_min), P_min (V_max) varies by 8.5 hPa (11.0 kt) between the 25th and 75th percentiles, and it varies by 17.1 hPa (22.6 kt) between the 10th and 90th percentiles; corresponding variations in the Dvorak Current Intensity (CI) numbers are also quantified. Also investigated is an adjusted WPR in which environmental conditions are incorporated through multiple linear regression. Its utilization reduces the variations to 6.9 hPa (9.5 kt) between the 25th and 75th percentiles and 13.0 hPa (18.9 kt) between the 10th and 90th percentiles. These remaining variations indicate intrinsic variability of WPR, suggesting a need for further utilization of observations to improve the intensity estimation of TCs.