The role of surface heat fluxes on the size of typhoon megi (2016)
Journal
Journal of the Atmospheric Sciences
Journal Volume
78
Journal Issue
4
Pages
1075-1093
Date Issued
2021
Author(s)
Abstract
This study attempts to understand how surface heat fluxes in different storm regions affect tropical cyclone (TC) size. The Advanced Research version of the Weather Research and Forecasting(ARW-WRF) Model (version 3.5.1) is used to simulate Typhoon Megi (2016). A series of numerical experiments are carried out, including a control simulation and several sensitivity experiments with surface heat fluxes suppressed in different TC regions [to mimic the reduction of the wind-induced surface heat exchange (WISHE) feedback in the inner and/or outer core]. The results show that with surface heat fluxes suppressed in the entire domain, the TC tends to be smaller. Meanwhile, the TC size is more sensitive to the surface heat flux change in the outer core than to that in the inner core. Suppressing surface heat fluxes can weaken the rainbands around the suppressed area, which in turn slows down the secondary circulation. When the surface heat flux is suppressed in the inner-core region, the weakening of the secondary circulation associated with the diminished inner rainbands is limited to the inner-core region, and only slightly affects the absolute angular momentum import from the outer region, thus having negligible impact on TC size. However, suppression of surface heat fluxes in the outer-core region leads to less active outer rainbands and a more substantial weakening of secondary circulation. This results in less absolute momentum import from the outer region and in turn a smaller TC. ? 2021 American Meteorological Society. All rights reserved.
Subjects
Hurricanes; Storms; Weather forecasting; Advanced researches; Control simulation; Numerical experiments; Secondary circulation; Surface heat fluxes; Tropical cyclone; Weather research and forecasting; Wind induced surface heat exchange; Heat flux; climate modeling; heat flux; mesoscale meteorology; numerical model; tropical cyclone; typhoon; weather forecasting
SDGs
Other Subjects
Hurricanes; Storms; Weather forecasting; Advanced researches; Control simulation; Numerical experiments; Secondary circulation; Surface heat fluxes; Tropical cyclone; Weather research and forecasting; Wind induced surface heat exchange; Heat flux; climate modeling; heat flux; mesoscale meteorology; numerical model; tropical cyclone; typhoon; weather forecasting
Type
journal article