Himawari-8/9 data processing

CEReS, Chiba university, Japan
October, 20 2017
November, 28 2018 modified

About Himawari-8/9

The Himawari-8/9 is a geostationary satellite launched on October 4, 2014 which has a new payload called the Advanced Himawari Imager (AHI). The specifications are improved from that of the imagers on board MTSAT's. In each 10-minute period, the AHI will scan the Full Disk once, the Japan Area and Target Area (ie. Tropical cyclone ) four times. Here we demonstrate the visualization of Himawari-8/9 grided data provided by CEReS/Chiba university.

The bands and sampling gradations

Table 1. Relation between CEReS gridded data and JMA's Himawari 8/9 bands
CEReS gridded data
Bands and Numbers
JMA's Himawari8/9 Bands sampling gradation Pixel x Line gridded resolution
EXT 01 Band 03 (0.64 μm) 2048/11bit 24000 x 24000 0.005 degree (approx. 500 m)
VIS 01 Band 01 (0.47 μm) 12000 x 12000 0.01 degree (approx. 1km)
02 Band 02 (0.51 μm)
03 Band 04 (0.86 μm)
SIR 01 Band 05 (1.6 μm) 6000 x 6000 0.02 degree (approx. 2km)
02 Band 06 (2.3 μm)
TIR 01 Band 13 (10.4 μm) 4096/12bit 6000 x 6000 0.02 degree (approx. 2km)
02 Band 14 (11.2 μm)
03 Band 15 (12.4 μm)
04 Band 16 (13.3 μm) 2048/11bit
05 Band 07 (3.9 μm) 16384/14bit
06 Band 08 (6.2 μm) 2048/11bit
07 Band 09 (6.9 μm)
08 Band 10 (7.3 μm) 4096/12bit
09 Band 11 (8.6 μm)
10 Band 12 (9.6 μm)

Common Specifications: Covered area: 85 E -- 205 E (155 W), 60 N -- 60 S (same as our gridded data for MTSAT2)
2byte "unsigned short" binary data without any header and footer, and "big endian" data order
Data reading orders: West to East (left to right) and North to South (up to down).
Stored binary data is: HS data thenselves (CCT count like).

All bands data separately compressed by bzip2 (*.bz2).

Preparation

Please prepare grads or GMT to visualize the data.

Processing the Hiamwari-8/9 Gridded data

The Hiamwari-8/9 gridded data is open to web at FTP server (ftp://hmwr829gr.cr.chiba-u.ac.jp) that directry is stratified by the year and month combined number directories (i.e. /201507/). The bands as ext (extension), vis (visible), tir (thermal infrared), sir (short wave infrared) are under the year month numberd directory.

For example, the data of July 7th, 2015 00:00(UTC) Band13 (10.4 micro meter) is as below.
ftp://hmwr829gr.cr.chiba-u.ac.jp/gridded/FD/V20151105/201507/TIR/201507070000.tir.01.fld.geoss.bz2
To download the data, confirm the full path includes file name that composed of date and band, use "wget" command. This instruction will continue with thermal IR band (band13, 10.4 micro meter).

 wget ftp://hmwr829gr.cr.chiba-u.ac.jp/gridded/FD/V20151105/201507/TIR/201507070000.tir.01.fld.geoss.bz2
The grided data that distributed from CEReS via FTP is compressed file by bz2 archive format. Extract it by "bunzip2" command.
 bunzip2 201507070000.tir.01.fld.geoss.bz2
The data file type is unsigned short integer, big endian binary. Most of personal computer CPUs such as x86_64 are supported a liitle endian while workstations such as Sun WS, PowerPC supported big endian. To byte swap the data order, use "dd" command with a byte swap option. If you use the -w option in xyz2grd command, you can skip this step.
 dd if=201507070000.tir.01.fld.geoss of=little-count.geoss conv=swab
Confirm the data value using "od" command with the option "-d" that means unsigned short. The output file "little-count.geoss" is a converted little endian data. Check the data value as follow.
 od -d -An -w2 little-count.geoss |sort 
The value will be shown with the range in 1 to 4096 (Band 13). To make an image of Himawari-8 data (count value), follow these bellow ways (GMT, GrADS).

Conversion count value into tbb

To convert from count value to tbb, execute sample program using lookup table. The convert program is available from count2tbb_v101.tgz.
 wget ftp://hmwr829gr.cr.chiba-u.ac.jp/gridded/FD/support/count2tbb_v101.tgz
 tar zxvf count2tbb_v101.tgz
 cd count2tbb 
The main source code count2tbb05.c, count2tbb10.c, and count2tbb20.c correspond to 500m resolution data (ext01), 1km resolution data (vis01-03), and 2km resolution data (sir01,02, tir01-10), respectively. The conversion look-up tables from count vale to tbb are ext.01, sir[01-02], and tir.[01-10], respectively. This time we demonstrate tir01 data of 2 km resolution, so we use count2tbb20.c program and lookup table tir.01.
 gcc count2tbb20.c -o c2t20.x
"c2t20.x" is an executable file to convert from count value to tbb. Move the little endian data (little-count.geoss) that you just prepared in the same directory, do the conversion as follows.
  ./c2t20.x little-count.geoss tir.01
Then a converted file "grid20.dat" appears, which is 4 bytes real tbb. Check the data value as follow.
 od -tf4 -An -w4 grid20.dat |sort 
"count2tbb.sh" is a shell code that collectively performs a series of conversion from data download to tbb conversion. Please take advantage to properly specify the time parameters and band.

Visualization with GMT ver.4 plot tool

Here, describes the procedure for displaying the count data (little-count.geoss). GMT setting: Set a bordar line as solid line.
 gmtset BASEMAP_TYPE PLAIN
 gmtset PAPER_MEDIA=a4+
 gmtset COLOR_BACKGROUND black
 gmtset COLOR_FOREGROUND white
 gmtset COLOR_NAN black

 gmtset FRAME_PEN=1.25p,0/0/0 #Frame color
 gmtset GRID_PEN_PRIMARY=0.10p,90/90/90 #Grid color
 gmtset TICK_PEN=0.5p,0/0/0 # tick font color
First, make a color pallet file. The "makecpt" is a utility that will help you make color palette tables. The color style is set to gray scale (-Cgray), the vale range is set to 0 to 4096, 410 steps. -Z option creates a continuous cpt file while default is discontinuous.
 makecpt -Cgray -T0/4096/410 -Z > count.cpt
Convert binary data to GMT type format.
The xyz2grd reads a z or xyz table and creates a binary grid file. -R (regional range) must be same as that of original dataset dimensions. -Z option sets exact specification of incoming 1-column z-table. If data is in row format, state if first row is at T(op) or B(ottom). Then, append L or R to indicate starting point in row. Then specify one of the following data types,
        c  signed 1-byte character.
        u  unsigned 1-byte character.
        h  signed short 2-byte integer.
        H  unsigned short 2-byte integer.
        i  signed 4-byte integer.
        I  unsigned 4-byte integer.
        l  signed long (4- or 8-byte) integer.
        f  4-byte floating point single precision.
        d  8-byte floating point double precision.
To swap byte-order in 2-byte words, append w in -Z option.
 xyz2grd 201507070000.tir.01.fld.geoss -Glittle-count.gmt -I0.02/0.02 -R85/205/-60/60 -F -N4096 -ZTLH
Here little_endian.gmt file is created. Once converted to GMT (netCDF) format, you do not need to do this again. Now draw the image.
The range (-R) is set to area you defined.
 grdimage little-count.gmt -JQ140/15 -Ccount.cpt -K -P -R85/205/-60/60 > ir1-count.eps
 pscoast -Ba20g20/a15g15eWSn -J -R -Di -K -N1/2t7.5_7.5:0/0/255/0 -W1/0/255/0 -O >> ir1-count.eps
 echo "140 62 18 0 0 CB Himawari-8 Band13 20150707 00:00UTC" |pstext -R -J -G0/0/0 -O -K -N >> ir1-count.eps
 psscale -D7.5/-1/12/0.5h -Ccount.cpt -B512/:"[count]": -O >> ir1-count.eps
Convert eps into png. -E option set to the density 300 dpi.
 ps2raster ir1-count.eps  -P -A -E300 -Qt -Qg -Tg && eog ir1-count.png
ir1-count.png will be created.

For GMT ver.5 users

GMT setting: Set a bordar line as solid line and define font size and title position.
 gmt set MAP_FRAME_TYPE plain
 gmt set COLOR_BACKGROUND black
 gmt set COLOR_FOREGROUND white
 gmt set COLOR_NAN gray
 gmt set PS_MEDIA a4
 gmt set FONT_TITLE 13p
 gmt set MAP_TITLE_OFFSET -0.2c
 gmt makecpt -Cgray -T0/4096/410 -Z > count.cpt
Convert binary data to GMT type format.
The xyz2grd reads a z or xyz table and creates a binary grid file. -R (regional range) must be same as that of original dataset dimensions. -Z option sets exact specification of incoming 1-column z-table. If data is in row format, state if first row is at T(op) or B(ottom). Then, append L or R to indicate starting point in row. Then specify one of the following data types,
        c  signed 1-byte character.
        u  unsigned 1-byte character.
        h  signed short 2-byte integer.
        H  unsigned short 2-byte integer.
        i  signed 4-byte integer.
        I  unsigned 4-byte integer.
        l  signed long (4- or 8-byte) integer.
        f  4-byte floating point single precision.
        d  8-byte floating point double precision.
 gmt xyz2grd little-count.geoss -Glittle-count.gmt -I0.02/0.02 -R85/205/-60/60 -r -di4096 -ZTLH
Here little_endian.gmt file is created. Now draw the image.
Draw the data. The range (-R) is set to area you defined.
 gmt grdimage little-count.gmt -JQ140/15 -Ccount.cpt -K -P -R85/205/-60/60 > ir1-count.eps
 gmt pscoast -BWSne+t"Himawari-8 Band13 20150707 00:00UTC" -Bxa20g20 -Bya20g20 -J -R -Di -K -N1/0.25p,0/255/0,solid -W0.25p,0/255/0,solid -O >> ir1-count.eps
 gmt psscale -D7.5/-1/12/0.5h -Ccount.cpt -B512/:"[count]": -O >> ir1-count.eps
 gmt psconvert ir1-count.eps  -P -A -E300 -Qt -Qg -Tg && eog ir1-count.png

For GrADS users

Save bellow script as grads.ctl.
 DSET little-count.geoss
 UNDEF  4098
 options YREV LITTLE_ENDIAN
 TITLE  Himawari8 count vale
 XDEF 6000 LINEAR 84.99 0.02
 YDEF 6000 LINEAR -60.01 0.02
 ZDEF  1 linear    1 1
 TDEF 1  LINEAR   00z7Jul2015 10mn
 VARS 1
 count 0 -1,40,2 Himawari8 count value
 endvars
For 4 bytes data, modify as the variable "count 0 99 Himawari8". open GrADS.
 grads -l
Type follow commands.
 open grads.ctl
 set grads off
 set gxout shaded
 set grid on 1 15
 set xlint 20
 set ylint 20

 set rgb 30 25 25 25
 set rgb 31 51 51 51
 set rgb 32 76 76 76
 set rgb 33 102 102 102
 set rgb 34 127 127 127
 set rgb 35 153 153 153
 set rgb 36 178 178 178
 set rgb 37 204 204 204
 set rgb 38 230 230 230
 set rgb 39 255 255 255

 set clevs  410 820 1230 1640 2048 2460 2870 3280 3690
 set ccols 30 31  32   33   34   35   36   37   38   39  

 set mpdset hires
 set map 3 1
 d count
 set strsiz 0.8 1
 draw title Himawari8 Band13 20150707 00:00UTC
 cbarn 
 printim ir1-count-grads.png  white  x1600 y1200
 !eog ir1-count-grads.png

Install GMT5.x.x on Centos7

yum install netcdf* GMT* gshhg-gmt-* -y 
Then install GMT4.x.x

Download the GMT4 source file.
tar jxvf gmt-4.5.18-src.tar.bz2

cd gmt-4.5.18
./configure --prefix=/usr/local/GMT4; make ; make install install-data install-man install-doc
ln -s /usr/share/gshhg-gmt-nc4 /usr/local/GMT4/share/coast
ln -s /usr/local/GMT4 /usr/local/gmt
export PATH=$PATH:/usr/local/gmt/bin