1
sity of
re than
to the
in the
ctober,
Indian
yclonic
no-rain
IAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring”, Hyderabad, India, 2002
region near Sri-Lanka; this may be due to the whirling of the
monsoon winds in that region.
MSMR Rainfall(mm/h) 1999-2001
A
Figure 4: Distribution of MSMR rainfall seasonally
It is interesting to note that even after the shift of ITCZ from
north to south, the rainfall amounts are more over the eastern
part of the Indian Ocean.
5. DISCUSSION
This has been a maiden attempt to present a climatology using
the data of Passive Microwave measurements from MSMR of
Indian Remote Sensing satellite IRS-P4. Due to the obvious
reasons of the limitations of the microwave sensors for its
resolution capabilities, it would be unreasonable to claim the
accuracy in absolute quantitative values of rainfall. However,
the features of ITCZ and monsoon progress are brought out
fairly well. In fact, it is interesting to note that with only three
low frequencies and dual polarized channels (10, 18 and 21
GHz) of MSMR, almost the similar features are brought out as
those from the low to high frequency channels (10 to 85 GHz)
of TRMM-TMI. Though no claim is being made about the
competitiveness of these two sensors, however the results from
MSMR does provide an opportunity to generate the monthly
maps, suitable for the study of displacement of the rain belts,
and of changes in the intensity of the ITCZ from month to
month. Several refinements are possible for the improvement of
the results. However, the overall rainfall results shows that it
could be used as inputs to numerical models and to studies of
planetary energy and water budgets. Continuing with this spirit,
the higher frequencies and resolutions from existing TRMM
sensors, and forthcoming Megha-Tropiques and GPM mission
sensors would be utilized with the objectives of many more
possible applications.
6. ACKNOWLEDGMENT
Authors are thankful to Dr. A.K.S. Gopalan, Director, SAC,
and Dr. M.S. Narayanan, Group Director, MOG/SAC for their
463
encouragement. Authors are also thankful to RSS/USA, and
EORC/NASDA for providing TMI/PR data.
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