IAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring”, Hyderabad, India, 2002 
  
MSMR Rainfall(mm/h) 1999 
  
  
  
Figure 2(a): Distribution of MSMR rainfall for 1999 
The average date of onset of South-West (S-W) monsoon over 
Indian peninsular region generally falls from 1 to 10 June every 
year. According to Indian Meteorological Department (IMD), 
the onset dates during these three years were 31 May, 1 June, 
and 23 May, respectively. Simultaneously the vigorous rainfall 
occurrences near the west costal regions are clearly represented 
in all the three years during the month of June by MSMR. 
The profuse rainfall over the Bay of Bengal gives a picture of 
the deep convective activities in the region. During the month 
of July, a large part of the monsoon circulation encompasses 
almost the entire Indian landmass. The sharp gradient of rainfall 
both over the Arabian Sea and the Bay of Bengal near the 
coastal regions in July closely corresponds to the expected 
development of monsoon over Indian subcontinent. Complete 
retreat of S-W monsoon is clearly evident in the month of 
November in all the three years. Simultaneously the shift of the 
ITCZ in the southern Indian Ocean is also evident. One of the 
prominent raining regions of highest rainfall in the globe has 
been the area near west coast of Sumatra, as is reported in mean 
annual precipitation map using Nimbus SSMR (by Prof. Dr. 
Rudolf Geiget) in atlas by Rao et al. (1976). The persistent 
rainfall observed by SSMR is also observable from MSMR in 
the same region. This provides one of the qualitative calibration 
points of rain results from the MSMR. 
Rain distribution over the Indian Oceanic region are also 
presented for 3 seasons, namely, monsoon (June-September), 
Post-monsoon (October-January) and Pre-monsoon (February- 
May) (Figure 3). 
462 
MSMR Rainfall(mm/h) 2000 
  
408 468 BOB 558 60 665 708 "6E 808 868 90E 965408 468 50E 668 80E 868 708 765 808 868 90E 958 
01 02 04 08 08 1 
  
Figure 2(b): Distribution of MSMR rainfall for 2000 
  
  
  
Figure 2(c): Distribution of MSMR rainfall for 2001 
It is quite evident that during monsoon season the intensity of 
rainfall in the Bay of Bengal region is significantly more than 
that of rain in Arabian Sea region. This may be due to the 
prominent circulation of Findlater Jet in this area than in the 
Arabian Sea region. It remains persistent throughout October, 
until the monsoon starts retreating to the southern Indian 
Ocean, and also due to the large-scale formation of cyclonic 
disturbances in this region. We can also find a circular no-rain