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Simulation of South Asian summer monsoon dynamics using REMO
Fahad Saeed, Stefan Hagemann and Daniela Jacob
Max Planck Institute for Meteorology, Hamburg, Germany. fahad.saeed@zmaw.de
1. Abstract
This study investigates the capability of regional climate
model REMO in simulating the South Asian summer
monsoon. The experiment consists of 40 year integration
from 1961 to 2000, with 0.5 degree resolution. The ability of
REMO to simulate the dynamics of the summer monsoon is
tested by comparing a number of fields with observations.
Surface and upper level circulation patterns yield results
close to ERA40 reanalysis. Simulated temperatures show a
warm bias over the Indian plains in comparison to
observations; however temperatures over the Tibetan
Plateau and along the coast are ably simulated. The model
captures the pattern of precipitation over Western Ghats and
over the plains but overestimates the precipitation in
Northern India and Bangladesh. The East-West oriented
precipitation pattern, at the border of India and Nepal is
more consistent in REMO than observational data
representing the sparse density of stations used for the
construction of observational fields in that region. Other
dynamical features like seasonal reversal of tropospheric
temperature gradient and strengthening of easterly vertical
shear compare well with observations. Further, summer
monsoon onset dates match reasonably well with the values
found in literature. The results indicate that the REMO
model can be a useful tool for examining the monsoon
behavior under climate change. This work is carried out
under WATCH project.