Examining the wintertime response to tropical convection over the Indian Ocean by modifying convective heating in a full atmospheric model

[1] The boreal winter response to tropical convection in the eastern Indian Ocean is investigated by increasing the mid-level diabatic heating for that region in the NCAR Community Atmosphere Model, version 3.1. The response is quite similar to the analytic Gill solution to steady heating, with a pair of Rossby wave packets poleward and to the west of the heating, extending into mid-latitudes, and a Kelvin response to the east of the heating. Changes to tropical convection in the eastern Indian Ocean are an important component of several important modes of atmospheric variability, including the Madden-Julian Oscillation, some El Nino-Southern Oscillation events, and the Indian Ocean Dipole. The simulated response has considerable similarities to observational aspects of these modes, both in terms of the Gill-like circulation patterns and changes to precipitation over Southwest Asia, demonstrating the central importance of the Indian Ocean convection in determining the regional response.