*NOTE; that the three-day running mean image is calculated from one-day mean data, and the date of the filename for daily image is defined as the middle day of the three-day average.
2) Data (binary)
You can get one-day mean and monthly mean data from the following anonymous FTP sites:
Item (1,1) stores the value centered at 0.0E and 38.0N
Item (1440,305) stores the value centered at 0.25W and 38.0S.
3) Resolution
Horizontal
0.25 deg (LON) x 0.25 deg (LAT)
Temporal
Daily and Monthly
4) Missing values
255
5) Conversion
You can calculate the real SST [C] from COUNT using the following relationship:
SST [C] = COUNT/10.0 + 10.0
*NOTE that SST values less than 10 [C] and exceeding 35.4 were defined as missing values.
4. Example program for F77
c
c TO READ TMI DAILY MEAN SST
c
parameter (idim = 1440, jdim = 305)
parameter (imiss = 255, rmiss = -999.0)
real*4 sst(idim,jdim)
character*1 csst(idim,jdim)
integer*2 isst
character c1(2)*1, c2*2
equivalence (c1,c2)
101 format (a2)
c OPEN DATA FILE
open(10,file='tmi_1day.19990101', access='direct',
2 form='unformatted', status='old', recl=idim*jdim, err=99)
c READ COUNT DATA
read(10,rec=1) csst
c CONVERT COUNT TO SST
do 100 i = 1, idim
do 110 j = 1, jdim
c1(2) = csst(i,j)
read(c2,101) isst
if (isst.eq.imiss) then
c MISSING
xsst(i,j) = rmiss
else
xsst(i,j) = real(isst)/10.0 + 10.0
endif
110 continue
100 continue
c CLOSE
99 close(10)
c STOP
stop
end
5. Display using GrADS
The Data is written in GrADS "non float data" format.
The Grid Analysis and Display System (GrADS) is an interactive desktop tool, which is available on almost UNIX workstations, Apple Macintosh, and DOS or Linux based PCs. You can get free GrADS software via anonymous ftp.
You can easily display 'TMISST (Ver. 1.0)' using the GrADS descriptor file:
Example for SST
DSET tmi_1day.19990101
TITLE TMI SST
OPTIONS yrev
UNDEF 255
XDEF 1440 LINEAR 0. 0.25
YDEF 305 LINEAR -38. 0.25
ZDEF 1 LEVELS 1000
TDEF 1 LINEAR 1jan1999 1dy
VARS 1
t1 0 -1,40,1 sst=t1/10+10
ENDVARS
For more information about GrADS, please read the GrADS documentation located on the GrADS Home Page.
6. References
Shibata, A., Imaoka, K., Kachi, M., and Murakami, H. (1999): Perspective of Researches using TRMM Microwave Imager. Journal of Remote Sensing Society of Japan, 18, 52-61. (In Japanese)
Shibata, A., Imaoka, K., Kachi, M., and Murakami, H. (1999): SST observation by TRMM Microwave Imager aboard Tropical Rainfall Measuring Mission. Umi no Kenkyu, 8, 135-139. (In Japanese)
7. Notice
1) If you want to use TMISST browse images in publications, please contact the EORC TRMM Office
(
).
2) If you use TMISST data in publications, please include the following credits:
"'TMISST (Ver. 1.0)' was produced and supplied by the Earth Observation Research Center, Japan Aerospace Exploration Agency."
Also, we would appreciate receiving a preprint and/or reprint of those publications utilizing TMISST data for inclusion in the TRMM bibliography. These publications should be sent to:
The EORC TRMM Office
Earth Observation Research Center
Japan Aerospace Exploration Agency
22nd Floor Office Tower X, Harumi Triton Square,
1-8-10, Harumi, Chuo-ku, Tokyo 104-6023, JAPAN
FAX: +81-3-6221-9192
3) Please contact us for any comments, problems or questions at e-mail
address:
).