Possible relation between land surface feedback and the post-landfall structure of monsoon depressions
Licensed under
Category
Published on
Abstract
The effect of pre-storm land surface on the monsoon
depressions (MDs) is studied. The Weather Research
Forecast (WRF) model was configured with two nested
domains to explore the sensitivity of MDs to antecedent
soil moisture and land surface representation for selected
three landfalling MDs during August 2006. Results indicate
that WRF had good ability to simulate the MDs, and the
post landfall model response was sensitive to antecedent
soil moisture and modestly dependent on land surface
representations. This was verified by reviewing the
climatology of 125 MDs (1970– 2003) which revealed that
if the surface received heavier rainfall a week ahead of MD
landfall, the inland intensity was maintained for a longer
duration. The gradient in surface heat fluxes as the depression
made landfall affected the evolution of the MDs over India. In
particular, warmer, wetter (cooler, drier) land surface can
intensify (weaken) the landfalling MDs over the Indian
monsoon region. Citation: Chang, H.-I., D. Niyogi, A. Kumar,
C. M. Kishtawal, J. Dudhia, F. Chen, U. C. Mohanty, and
M. Shepherd (2009), Possible relation between land surface
feedback and the post-landfall structure of monsoon depressions,
Geophys. Res. Lett., 36, L15826, doi:10.1029/2009GL037781.