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30/09/2008 T. Kubota, presented at AIT, Bangkok

TRMM Data Handling

Takuji Kubota

Earth Observation Research Center (EORC)

Japan Aerospace Exploration Agency (JAXA)

E-mail: [email protected]


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Contents

TRMM Data Overview

Analyzing ToolsTutorial for PPS Orbit Viewer


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TRMM Da ta Ove rv iew


4/40430/09/2008 T. Kubota, presented at AIT, Bangkok

Standard Product

Operational product that produced at JAXA Earth Observation Center(EOC) and NASA/GSFC Precipitation Processing System (PPS)(formerly, TRMM Science Data and Information System (TSDIS)).

Other products

Subset Product

Sub-set of specific region or area, produced from standard product.

Research Product

Product that uses research algorithm and is produced mainly for researchobjectives. Products are not produced operationally.

Near Real-time Product (Level 1 and 2)

Product that is released in near real-time in order to meet requirement for

operational uses, such as numerical weather prediction. Products are releasedwithin 3-to-4 hours after satellite observation to operational agencies, but datainformation was reduced and geolocation accuracy could be worse than standardproduct in several kilometers. Need authorization of NASA to access.

Near Real-time Product (Level 3)

3-hourly global rainfall products at 0.25 deg. grid boxes.

TRMM Product



Transferred from TRMM

Quality checked raw data

Calibrated data (PR receivedpower etc.)

Temporary and spatially

averaged (monthly mean rainfall)

Geophysical parameters (rain rate,

etc.)

Raw dataRaw data

Level 0Level 0

Level 1Level 1

Level 2Level 2

Level 3Level 3

Data Processing for Standard Products

Instantaneous

Monthly, or 3-hourly



ProcessingProcessingLevelLevel

(0 - 3)

2 A 2 5

SensorSensor 0 - 50: VIRS

1: TMI

2: PR

3: TRMM Combined

4: TRMM & Other Sources5: GV

Level TypeLevel Type(A - C)

AlgorithmAlgorithm

NumberNumber

1 - 6

Point CERES and LIS products

have different naming rules

because they are processedand distributed by other

NASA Centers.

Standard Product Naming Rules



Level description

0Data transmitted from satellite to ground stations is now set alongwith timeline, quality checked, and redundancy part is deleted.

1Sensor specific parameter (radar reflectivity, brightness temperature,etc.), adding ancillary data and geolocation information to Level 0 andusing sensor calibration results.

2

Retrieved geophysical parameters (rain rate, water vapor) , processing

Level 1 data using variety of algorithms. 2-D or 3-D snap shot alongwith TRMM orbit.

3

Spatially and temporally averaged/accumulated geophysicalparameter produced from Level 2 data.

2 A 2 5

Not distributed to publicPoint

Point Sensor specific parameter

Point Retrieved geophysical parameter

Point Spatially and temporally mean of Level 2

Processing Level



Level 1 Products

Data Product Description

1B01: Visible and InfraredRadiance (VIRS)

Calibrated VIRS (0.63, 1.6, 3.75, 10.8, and

12 um) radiances at 2.2 km resolution overa 720 km swath

1B11: Microwave Brightness

Temperature (TMI)

Calibrated TMI (10.65, 19.35, 21, 37, and

85.5 GHz) brightness temperatures at 5 to45 km resolution over a 760 km swath

1B21: Radar Power (PR)

Calibrated PR (13.8 GHz) power at 4 km

horizontal, and 250 m vertical, resolutions

over a 220 km swath

1C21: Radar Reflectivity

(PR)

Calibrated PR (13.8 GHz) reflectivity at 4

km horizontal, and 250 m vertical,

resolutions over a 220 km swath



Level 2 Products

Data Product Description

2A12: Hydrometeor Profile

(TMI)

TMI Hydrometeor (cloud liquid water, prec. water,

cloud ice, prec. ice) profiles in 14 layers at 5 km

horizontal resolution, along with latent heat andsurface rain, over a 760 km swath

2A21: Radar Surface Cross-

Section (PR)

PR (13.8 GHz) normalized surface cross-section

at 4 km horizontal resolution and path attenuation

(in case of rain), over a 220 km swath

2A23: Radar Rain

Characteristics (PR)

Rain type; storm, freezing, and bright band

heights; from PR (13.8 GHz) at 4 km horizontal

resolution over a 220 km swath

2A25: Radar Rainfall Rate and

Profile (PR)

PR (13.8 GHz) rain rate, reflectivity, andattenuation profiles, at 4 km horizontal, and 250 m

vertical, resolutions, over a 220 km swath

2B31: Combined RainfallProfile (PR, TMI)

Combined PR/TMI rain rate and path-integrated

attenuation at 4 km horizontal, and 250 m vertical,resolutions, over a 220 km swath



Level 3 ProductsData Product Description

3A11: Monthly 5 x 5 Oceanic

Rainfall

Rain rate, conditional rain rate, rain frequency, and freezing height for

a latitude band from 40 degree N to 40 degree S, from TMI

3A12: Monthly 0.5 x 0.5 mean2A12, profile, and surface rainfall

0.5 x 0.5 degree gridded monthly product comprised of mean 2A12

data and calculated vertical hydrometeor profiles as well as mean

surface rainfall

3A25: Monthly 5x5

and .5x.5 Spaceborne RadarRainfall

Total and conditional rain rate, radar reflectivity, path-integrated

attenuation at 2, 4, 6, 10, 15 km for convective and stratiform rain;

storm, freezing, and bright band heights, and snow-ice layer depth for

a latitude band from 40N to 40S, from PR

3A26: Monthly 5 x 5 Surface

Rain Total

Rain rate probability distribution at surface, 2 km, and 4 km for a

latitude band from 40N to 40S, from PR

3B31: Monthly 5 x 5

Combined RainfallRain rate, cloud liquid water, rain water, cloud ice, grauples at 14

levels for a latitude band from 40 degree N to 40 degree S, from PR

and TMI

3B42: 3-Hour 0.25 x 0.25

merged TRMM and other satelliteestimates Calibrated IR merged with TRMM and other satellite data

3B43: Monthly 0.25

x 0.25

merged TRMM and other sourcesestimates Merged 3B-42 and rain gauge estimates



Level 0

1B21 1C21

2A21 2A25 2A23

PR Observation at each Level



Level 3Level 1 and Level 2

startend

scaling up

0

0

40N

40S

0

0

Data is set in certain grid size in global

area, averaged in certain period.

Data is set in

sequence as TRMM

observed for each

orbit.

Note that PR product also has vertical array.

Level and Data Array


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49 pixel

1

40

pixel

approx

.900

0sc

an(for

1gran

ule)

49 pixel

80p

ixel

approx

.900

0scan

(for

1granu

le)

surface

Level 1Level 2

Point Data matrix for vertical direction is stored

from upper (higher altitude) to lower.

Altitude of Level 2 data was corrected.

Slice

Slice

TRMM/PR Data Structure

surface


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3A25 data

Monthly mean rainrate (mm/h)

Rain count numberTotal count number

Monthly mean rain rate (mm/h)

[unconditional]

Mean rain rate x(Rain count number/Total count)

Daily accumulated rain (mm/day)

Monthly mean rain rate x 24

Monthly accumulated rain

(mm/month)Daily accumulated rain

x Number of days of month

3A25: PR Monthly Rainfall


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HDF-EOS FormatHDFHierarchical Data Format, SpecifiyingSatellite observation.

Structure of HDF Format

Metadata + Scientific Data Sets (SDS) + V

data

Category Characteristics Example

Metadata Detailed description of file in textformat

algorithm version,

pixel count number,etc.

SDSScientific Data Setsmulti-dimension matrix dataconsisting from data elements insame type

radar reflectivityrain

Vdata table data which can combinedata in different type data by each scan

Data Format


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Orbit maintenance maneuver (Delta-V maneuver)

To keep satellite altitude at appropriate range.

Currently, operated once in 7-10 days.

180 degree yaw maneuver

To avoid VIRS radiation cooling unit to go sun side.

Operated once in 2-4 weeks

90 degree yaw maneuver

To assess PR cross-track antenna pattern.

Operated once in half year.

Since satellite flying direction is reversed at this

maneuver, scan direction is also reversed. Need tocheck geolocation of each scan data in the same time.

Point

maneuver

Note for data handling (1)


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Flying direction

12

3

123

760km

Flying direction

180-degree Yaw Maneuver


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Other factor for erroneous observation

Radio interference

example in Australia, etc.

Natural phenomena

Leonid meteor shower, etc.

Sensor maintenance

operated in non-observation mode

Trouble in solar array panel

VIRS stopped operation from 6 Sep. to 17 Oct. 2002

PR is not observe these

area because the same

frequency to PR is used in

the ground.

Point

Note for Data Handling (2)


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PR Level 3 product for August 2001 was made from about 13days (1-7 Aug. and 25-31 Aug.) eliminated data during altitude

rising period

Data version number was changed to 5A post-boost.

Altitude oforbit

Start date &orbit number

End date &orbit number

Data distribution

350km2001/8/1

211642001/8/7

21267YES

Altitude risingperiod

2001/8/721268

2001/8/2421540

Empty granule

402.5 km2001/8/25

215412001/8/31

21649YES

TRMM altitude change

Observation in August 2001 is;

Point Note that using data in different version number.

Version number is confirmed from file name.

Note for Data Handling (4)


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Ana ly zing Too ls


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How to Get the TRMM Online Data (1)PR/TMI/VIRS Data

DAAC (Goddard Distributed Active Archive Center - NASA/GSFC)

http://disc.sci.gsfc.nasa.gov/data/datapool/TRMM/

Level 1, 2, 3 standard products available

Precipitation Processing System (PPS) - NASA/GSFC

http://pps.gsfc.nasa.gov/

PPS Toolkit, HDF information

Gridded text data (3G68) available

(ftp://trmmopen.gsfc.nasa.gov/pub/)LIS (Home Page/download data)

http://thunder.msfc.nasa.gov/

TRMM Realtime System

http://pps.gsfc.nasa.gov/trmmrt/index.htm

TRMM 3 Hourly Global Rainfall - NASA/GSFC

http://trmm.gsfc.nasa.gov/

Near real-time 3-hourly rainfall data (3B40RT, 3B41RT, 3B42RT)


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How to Get the TRMM Online Data (2)

EOC home page JAXA/EOC

http://www.eorc.jaxa.jp/en/about/distribution/index.html

Satellite information and images, data order

EORC TRMM home page - JAXA/EORC

http://www.eorc.jaxa.jp/TRMM/index_e.htm

TRMM data in Asia monsoon and Japan area

Tropical cyclone databaseTRMM Realtime Tropical Cyclone Monitoring (images only)

GSMaP_NRT home page - JAXA/EORC

http://sharaku.eorc.jaxa.jp/GSMaP/index.htm

Research Product

C and FORTRAN Programming to


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C and FORTRAN Programming toHandle Standard Products

TRMM data has been produced as the format of HDF version 4.

To read HDF files using your programs written by either C orFOTRAN, you need to install HDF library on your environment,

which freely provided by NCSA (http://hdf.ncsa.uiuc.edu).

To help the users of the TRMM products, PPS has provided thePPS/TSDIS Science Algorithm Toolkit based on the HDF library

(http://pps.gsfc.nasa.gov/tsdis_redesign/software.html).The toolkit provides routines for reading and writing data to andfrom the HDF files; routines are provide for Level 1-3 productsand for both satellite and GV. Each of the routines in the toolkitare callable in either C or FORTRAN. The toolkit also includesroutines for reading land/sea data and topographical data.


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Before ProgrammingInstall of HDF Library

ftp://ftp.ncsa.uiuc.edu/HDF/HDF/HDF_Current/bin/

Download library for your computer OS and install

Install of PPS/TSDIS Toolkithttp://pps.gsfc.nasa.gov/tsdis/tsdistk.html

Download PPS/TSDIS Toolkit and install

Download elevation/land-sea data and install

Download tutorial (Tutorial for Reading TRMM

Data Products), file specification (TSDIS-TSUInterface Control Specification) and sampleprograms for C and FORTRAN

http://pps.gsfc.nasa.gov/tsdis_redesign/SelectedDoc

s.html


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TRMM Analysis Tool

PPS/TSDIS Orbit ViewerFor quick look. Easy to make browse image.

For UNIX, Linux and Windows.

Demonstration later.

NCSA HDF LibraryC and FORTRAN library for reading and writing HDFformat data.

For UNIX and Linux.

PPS/TSDIS ToolkitC and FORTRAN library based HDF Library.

For TRMM data (PR,TMI,VIRS,COMB,GV) only.

For UNIX and Linux.


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TRMM 3 hourly Global Rain Map in GSFC

http://trmm.gsfc.nasa.gov/

Latest 3 Hourly Global Rainfall

Latest Week of Global Rainfall Accumulation

ResearchProduct in

NASA/GSFC

(for GPM)

3B40RT:

TMI+SSMI

3B41RT:

Geo-stationary

IR data

3B42RT:

TMI+SSMI+IR

Online dataavailable withinnear-real time

(

6 hours)

JAXA/EORC Tropical Cyclone Database


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Browse images, 3D movies

and data of tropicalcyclones observed by

TRMM, Aqua/AMSR-E,

Midori-II/AMSR are

available.

JAXA/EORC Tropical Cyclone Database(for TRMM, AMSR-E and AMSR)

http://sharaku.eorc.jaxa.jp/TYP_DB/index_e.shtml

TRMM Tropical Cyclone Real-time
http://sharaku.eorc.jaxa.jp/TYP_DB/index_e.shtmlhttp://sharaku.eorc.jaxa.jp/TYP_DB/index_e.shtml


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TRMM Tropical Cyclone Real-timeMonitoring

Near real-time browseimages of tropical

cyclones (typhoons)observed by TRMM isavailable.

http://www.eorc.jaxa.jp/TRMM/NRTtyphoon/index_e.htm
http://www.eorc.jaxa.jp/TRMM/NRTtyphoon/index_e.htmhttp://www.eorc.jaxa.jp/TRMM/NRTtyphoon/index_e.htm


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PPS/TSDIS Orbit Viewer

PPS/TSDIS Orbit ViewerFor quick look. Easy to make browse image.

For UNIX, Linux and Windows.

Demonstration later.

http://pps.gsfc.nasa.gov/TSDISorbitViewer/release.html


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Tuto ria l fo rPPS O rb it Viewe r


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Install Viewer and Datasets

Insert CD-ROM

Open OrbitViewer folder and click

orbit.1.3.6_winXP32bit.exe file forinstalling

Tutorial text provide by PPS/TSDIS is in

a same folder TRMM_orbit.zip and TC_DB.zip arecompressed. Copy them to your PC anduncompress them.


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Look at Data Sample (1)In the directry TRMM_orbit,

1B01.071005.56330.6.HDF

(VIRS)

1B11.071005.56330.6.HDF

(TMI Brightness Temperature)

2A12.071005.56330.6.HDF

(TMI rain rate)

2A25.071005.56330.6.HDF

(PR Rain rate)

3A25.071001.6A.HDF(Monthly PR Rain rate)


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Look at Data Sample (2)

TC_DB folder includes 12 sampledata of TRMM archived at JAXA/EORC

Tropical Cyclone Database

1B01...HDF (VIRS)

1B11...HDF (TMI Brightness Temperature)

2A12...HDF (TMI rain rate)2A25...HDF (PR Rain rate)

See images in TC_DB/list for your

reference.


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TC_DB List (1)


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TC_DB List (2)

l h il


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Google Earth Files

kmz_files in the CD-ROM is for theGoogle Earth.

You can view these files by an install ofthe Google Earth.

http://earth.google.com/intl/en/

Time control bar: click for time step.

You can see movies about

this in the directryGSMaP_movie.

L i !


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Lets practice !

1. Install the orbit viewer.

2. Start orbit viewer.

3. Open TRMM_orbit/2A25.071005.56330.6.HDF.

4. Select e_SurfRain in Arrays.

5. Click east of Philippines in the bottom panel.

6. Click anywhere in the PR path.7. You can save images by Orbit viewer.

8. Next step: see Figure 3.1, 3.4, 3.5, and 3.7 in

Tutorial text.9. Further step: open other HDF files in the CD-

ROM.

+++trmm data handling.pdf

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