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Section 4
OUTLINE OF THE TRMM PRODUCTS
a. Module 1:
1) Initialize all sums
2) Ingest 2A12 and 2B31 overlap region. The details depend upon TSDIS, but the algorithm
needs the orbit numbers for first and last orbit of the month
3) Derive adjustment ratios
b. Module 2
The second module consists of adding the TMI 2A12 and then applying the adjustment ratio
1) Sum the hydrometeors while counting the number of overpasses
2) Calculate monthly accumulations
3) Apply adjustments
4) Write output
(b) Input Data of 3B31 Processing
For 3B31 processing, TMI 2A12 and PR 2B31 are input, and the following reference data is
necessary for processing of TMI data.
< Supplied by TSDIS >
- Land/Ocean database with 4 km resolution
(c) Output Data of 3B31 Processing
The outputs of 3B31processing are listed in below.
- Surface Rain (TMI) [mm]
sfcrainTMI
: Surface rain from 2A12 monthly accumulated in each 5˚ x 5˚ grid.
- Surface Convective Rain (TMI) : Convective surface rain from 2A12 monthly accumulated in each 5˚
[mm]
x 5˚ grid.
convectRain
- Surface Rain (Comb) [mm]
sfcrainCOMB
: Surface rain from 2B31 monthly accumulated in each 5˚ x 5˚ grid.
- Precipitation Water (Comb) [g/m3]
rainWaterCOMB
: Monthly mean rain water at each vertical layer from 2B31 in each
5˚ x 5˚ grid.
- Surface Rain (Overlap) [mm]
sfcrainTMIoverlap
: Surface rain from 2A12 where 2A12 and 2B31 overlap monthly
accumulated in each 5˚ x 5˚ grid.
- Surface Convective Rain
(Overlap) [mm]
convectRainoverlap
: Convective surface rain from 2A12 where 2A12 and 2B31 overlap
monthly accumulated in each 5˚ x 5˚ grid.
- Surface Rain (Overlap/Comb) [mm]
sfcrainCOMBoverlap
: Surface rain from 2B31 where 2A12 and 2B31 overlap monthly
accumulated in each 5˚ x 5˚ grid.
- Ratio of Surface Rain
surfAdjRatio
: The ratio of 2B31 to 2A12 surface rain fall, calculated from the
swath overlap region for each 5˚ x 5˚ grid.
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