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 644

Fig. 26.2 Analysis increment at 850 hPa in the wind speed of ( a ) MODIS, ( b )ATOVSand
( c ) SSM/I for 19-22 September 2006 depression

26.4.1.2 Results and Discussion

Initial Conditions

The impact of assimilation of satellite observations on the initial conditions can be
obtained by calculating the analysis increment. Analysis increment can be defined
as the difference in the model variables before and after the assimilation of the
observations. It does not give a qualitative or quantitative verification whether the
initial condition from satellite data assimilation is better or worse, but provides a
measure of how much the observation impacted the initial analysis. Figure 26.2