Studies on the Impacts of 3D-VAR Assimilation of Satellite Observations on the Simulation of Monsoon Depressions over India - Data Assimilation for Atmospheric, Oceanic and Hydrologic Applications - page 685

Fig. 26.26 Bias score for 48-h accumulated precipitation for CTRL, ATOVS, SSM/I and MODIS
for 18-22 June 2007 depression

Improvement Parameter ( ˜ )

The spatial distribution of shows almost identical features in all the three

assimilation experiment which is evident from Fig. 26.27 . The first day of forecast
witnessed negligible improvement in the rainfall features simulated by all the
assimilation experiments. The second day did show some positive improvement over
the peninsular region of the Indian subcontinent.

˜

RMSE of Temperature Profiles

The RMSE values of temperature in vertical are shown in Table 26.8 for the 18-22
June 2007 depression. Lower RMSE values of temperature are seen in 950, 920,
700, 300 and 200 hPa levels for the ATOVS experiment when compared to the
CTRL run, while the MODIS run shows lower RMSE of temperature at 780, 620
and 300 hPa levels. The SSM/I run shows improvement in the temperature forecast
at 950, 920, 850, 500, 400, 300 and 200 hPa levels on 20 June 2007 12 UTC when
compared to the CTRL run. On 21 June 2007 12 UTC, the ATOVS and the MODIS
experiments show improved temperature forecast for 6 levels in the vertical, while
the SSM/I run shows lower RMSE of temperature for 3 levels only. On 22 June 2007