Footprint of Tropical Cyclone Cold Wakes on Top‐of‐Atmosphere Radiation
Jishi Zhang, Yanluan Lin, Zhanhong Ma
Abstract
Abstract A recent study noted reduced rainfall and cloud fraction over cold wakes induced by tropical cyclones, but a quantification of top‐of‐atmosphere (TOA) radiation change due to these cold wakes has not been attempted. Based on global TOA radiative flux observations, we show that TOA shortwave and longwave radiations increase by 0.76 W m −2 (0.2%) and 0.74 W m −2 (0.3%) over the cold wake area relative to local climatology, respectively. Due to the cancelation between the shortwave and longwave components, daily average TOA net radiation is only marginally modulated by cold wakes, but stands out in the day and night time average. In addition, the seasonal basin‐wide regulation of TOA net radiation by cold wakes can be up to 1.0 W m −2 , locally comparable to the magnitude of radiative forcing due to man‐made aerosols. The regional impact of cold wakes on TOA radiations is therefore highly relevant and potentially important.