GPM Data Utilization Handbook

Version 5.1

March, 2024
JAXA

GPM Data Utilization Handbook

Preface
Global environment change has become a worldwide concern in recent years. For such issues,
aiming applications to the fields closely linked with our lives such as weather forecast and flood
forecast as well as for climate research but with utilizing observation technology by satellite, Global
Precipitation Measurement: GPM project has been in the works under international cooperation. The
GPM project is follow-on and expansion of the Tropical Rainfall Measuring Mission (TRMM) satellite,
and significantly enhances observation range and frequency by cooperation with a constellation ofseveral other satellites developed by each international partner. The GPM core satellite has been
cooperatively developed by the National Aeronautics and Space Administration (NASA) and Japan
Aerospace Exploration Agency (JAXA), and carries a Dual-frequency Precipitation Radar (DPR),
which has been jointly developed by JAXA and the National Institute of Information andCommunications Technology (NICT) and GPM Microwave Imager (GMI), which has been developedby NASA.
The Global Precipitation Measurement (GPM) Core Satellite was launched by H-IIA Launch Vehicle
No.23 at 3:37 a.m. on February 28, 2014 (Japan Standard Time, JST) from the Japan Aerospace
Exploration Agency/Tanegashima Space Center, and has gone into a circular orbit of altitude 407 km,
inclination angle 65° and period approx. 90 min. The data from GPM Core Satellite are received at theNASA ground station via Tracking and Data Relay Satellite System (TDRSS), and some of observation
data are transmitted from NASA Goddard Space Flight Center (GSFC) to JAXA/Tsukuba Space Center.
The data processing has been performed at both NASA and JAXA.
After the end of the initial functional verification phase, the GPM products of Level 1 to Level 3
have been opened for public access online at JAXA Earth Observation Satellite Data Distribution
System “G-Portal” (https://gportal.jaxa.jp/gpr/) from September 2014. We are updating GPM products
by improvement algorithms and continuously calibration and validation. In addition, we havereprocessed GPM and TRMM product which is long-term data set.
The GPM Core satellite is planning a controlled re-entry (the return of a spacecraft into Earth's
atmosphere) after the mission ends, and it is necessary to secure fuel for this purpose. As it wassuggested that the mission might end earlier than expected, NASA and JAXA performed two orbit
boost maneuver operations in November 2023. After the operations, it flight at an altitude ofapproximately 442km, and based on the amount of fuel remaining, that satellite lifespan has beengetting longer until around 2030.
The purpose of this handbook is to provide necessary information regarding the use of the GPM
products. We wish the GPM products with this handbook utilize your studies on enhancement ofclimate change analysis, as well as the operational uses.
March, 2024
Japan Aerospace Exploration Agency
Satellite Applications and Operations Center
Earth Observation Research CenteriGPM Data Utilization Handbook

Contents
INTRODUCTION ............................................................................................... 1-1
1.1. PURPOSE .............................................................................................................. 1-1
1.2. SCOPE................................................................................................................... 1-1
1.3. OVERVIEW OF GPM PROJECT ................................................................................ 1-1
GPM/TRMM SATELLITE SYSTEM ....................................................................... 2-1
2.1. OVERVIEW OF THE GPM SPACECRAFT ................................................................... 2-1
2.1.1. GPM Project ............................................................................................................................... 2-1
2.1.2. Outline of GPM Core Satellite ................................................................................................... 2-2
2.1.3. Outline of GPM Constellation Satellites .................................................................................... 2-4
2.2. OUTLINE OF GPM MISSION CRITICAL DEVICES...................................................... 2-6
2.2.1. The Dual-frequency Precipitation Radar (DPR) ........................................................................ 2-6
2.2.2. The GPM Microwave Imager (GMI) ....................................................................................... 2-10
2.3. OVERVIEW OF THE TRMM SPACECRAFT ............................................................... 2-13
2.3.1. Outline of TRMM Satellite ...................................................................................................... 2-13
2.4. OUTLINE OF TRMM MISSION CRITICAL DEVICES .................................................. 2-15
2.4.1. Precipitation Radar (PR) .......................................................................................................... 2-15
2.4.2. TRMM Microwave Imager (TMI) ........................................................................................... 2-16
2.4.3. Visible and Infrared Scanner （VIRS）.................................................................................. 2-17
2.4.4. Clouds and the Earth's Radiant Energy System （CERES）.................................................. 2-18
2.4.5. Lightning Imaging Sensor （LIS） ........................................................................................ 2-19
2.5. OUTLINE OF GROUND SYSTEM ............................................................................ 2-21
2.5.1. GPM Ground System and data flow......................................................................................... 2-21
GPM PRODUCT ................................................................................................ 3-1
3.1. OUTLINE OF THE PRODUCTS ................................................................................. 3-1
3.1.1. Scene Definitions ....................................................................................................................... 3-1
3.1.2. Definition of GPM Processing Levels........................................................................................ 3-5
3.1.3. Processing Diagram.................................................................................................................... 3-6
3.1.4. Products ...................................................................................................................................... 3-9
3.1.5. File Naming Conventions ......................................................................................................... 3-21
3.1.6. Products Format ....................................................................................................................... 3-32
3.1.7. Conceptual Explanation of Product/Algorithm Versions ......................................................... 3-35
3.2. PROCESSING DESCRIPTION .................................................................................. 3-36
3.2.1. DPR Product............................................................................................................................. 3-36
3.2.2. Global Satellite Mapping of Precipitation ................................................................................ 3-41
3.2.3. PR Product................................................................................................................................ 3-42
3.3. CALIBRATION AND VALIDATION .......................................................................... 3-44
3.3.1. Calibration ................................................................................................................................ 3-44
3.3.2. Validation ................................................................................................................................. 3-45
3.3.3. Calibration of TRMM .............................................................................................................. 3-53

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GPM Data Utilization Handbook

GETTING GPM PRODUCTS AND IMAGES ............................................................ 4-1
4.1. SERVICE DESCRIPTIONS ........................................................................................ 4-1
4.1.1. Getting Standard Products .......................................................................................................... 4-2
4.1.2. Getting Research Products ......................................................................................................... 4-5
4.1.3. Browsing Images and Results of Application Researches.......................................................... 4-7
4.1.4. Operational Information on the Satellite and Sensors .............................................................. 4-11
4.1.5. Usage Note ............................................................................................................................... 4-13
UTILIZATION OF GPM/TRMM DATA .................................................................. 5-1
5.1. DATA VISUALIZATION TOOLS ................................................................................ 5-1
5.1.1. THOR ......................................................................................................................................... 5-1
5.1.2. HDFVIEW ................................................................................................................................. 5-3
5.2. DATA ANALYSIS TOOLS ......................................................................................... 5-5
5.2.1. TKIO .......................................................................................................................................... 5-5
5.2.2. h5dump ....................................................................................................................................... 5-8
5.2.3. HDF Explorer ............................................................................................................................. 5-8
5.3. FILE FORMAT CONVERSION TOOL ......................................................................... 5-9
5.3.1. Earth Observation Satellite Data Format Conversion Tool ...................................................... 5-10
5.4. SAMPLE PROGRAM .............................................................................................. 5-11
APPENDIX 1 ACRONYMS .................................................................................................1
APPENDIX 2 ASSOCIATED INFORMATION ........................................................................ 1
A2.1 Reference Website ....................................................................................................................... 1
A2.2 Contact information ........................................................................................................................ 2
APPENDIX 3 OVERVIEW OF GPM PRODUCTS ................................................................. 1

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GPM Data Utilization Handbook

Change History
revision
Version
1.0
Version

date
Sept. 2nd 2014
Mar. 1st 20162.0

sectioncontent, reason-

The first edition

p.i

Update of the GPM product version 4

p.2-4,2-5

Update of the table of the list of the Constellation Satellites.

p.2-8,2-9

Update of the table of DPR operation mode.

p.4-1

Addition of the definition of GPM product level, GPM
L2,3 data processing, spectral latent heating, the GPM
Comb DPR/GMI L3 convective stratiform heating
information and the component factor of data group.

p. 4-2

Addition of the spectral latent heating product and update
file size, scene definition and frequency.

p.4-4~4-8

Revise product size and file size.

p.4-9

Addition of the scene unit definitions of NRT GMI, NRT
GPM and NRT DPR/GMI COMB products.

p．4-10~4-18

Addition of the GSMaP L3 (Hourly, Monthly), DPR L3(Daily, Monthly) and GPM spectral latent heating L2/L3
standard (STD) Products and KuPR/KaPR/DPR
Environment Auxiliary (ENV) Products information.

p.4-19Addition of the Algorithm key in table 4.1-17 and the
explanations of L3 Algorithm and Grid.

p. 4-27

Addition of the providing time of NRT products.

p.4-31

Addition of the external calibration information in the table
4.9-1 and table 4.9-2.

p.5-7

Addition of GPM/DPR and GMI in the EO satellite list.

P6-5~6-12

Revise data analysis tools and format conversion tools,
addition of sample program

Version
2.1

May. 26th 2017

All

Correction of the sentences.

P.2-4

Addition of the operation termination of the Defense
Meteorological Satellite Program (DMSP) F19.

P.4-7

Removal of DMSP F19 SSMIS Level 1CR.

P.4-9~4-10

Addition of the image of scene definition.

P.4-6

Addition of the GSMaP products (netCDF format).

P.4-19Addition of the file naming convention of GSMaP standard
products (netCDF format).

P.4-32Update of the GSMaP algorithm flow.

P.4-41~4-45

Reflect the product evaluation of GPM product version 5.

APPENDIX 2-2

Updated the e-mail address of contact point.

P.4-7

Removal of DMSP F19 SSMIS Level 1CR.

iv

GPM Data Utilization Handbook

revision

date

sectionVersion

Oct. 3rd 2017

P.1-1

3.0

content, reason
Update the sections description.

P.2-12~P.2-13

Addition of “2.3. Overview of the TRMM Spacecraft”

P.2-14~P.2-19

Addition of “2.4. Outline of TRMM Mission Critical
Devices”

P.2-20~P.2-21

Addition of “2.5. Outline of ground system”-

Removal of “OUTLINE OF GPM GROUND SYSTEM”.

P.3-1~P.3-6

Addition of “3.1.1. Scene Definitions”

P.3-6

Addition of “3.1.2 Definition of GPM Processing Levels”

P.3-8~P.3-9

Addition of “the processing flow of TRMM” into figure
3.1-5

P.3-10~P.3-15

Update of product name of table 3.1-3 and 3.1-4

P.3-16~P.3-17

Addition of “List of Standard TRMM Products” into table
3.1-5

P.3-18~P.3-29

Update of “3.1.5. File Naming Conventions”

P.3-29~P.3-31

Addition of “3.1.6 Definition of GPM Processing Levels”

P.3-32

Addition of “3.1.7. Conceptual Explanation of
Product/Algorithm Versions”

Version 3.1

July 2nd 2018

P.3-33~P.3-38

Update of “3.2 Processing Description”

P.3-39~P.3-40

Addition of “3.2.3. PR Product Processing”

Appendix 4-1

Addition of “TRMM PRODUCT LIST AND CAVEAT”

P.4-1~P.4-10

Update of “4.1. Service Descriptions” by renewal of GPortal (earth observation data providing system)

Version
4.0

Dec 6th 2021

P.4-10

Removal of 4.2. Usage of the Data Distribution Service

P.2-2, Table 2.2-1, P2-

Addition of information for KaPR scan pattern changes.

7, P.3-2, P3-3, P3-38
Deletion F20 of SSMIS and update of information for

P.2-4, 2-5

ATMS/JPSS.
Correction of scene definition of L1/L2 products.

P.3-1

Addition of sampling resolution/

Table 3.1-3

grid size and partially correction.
Correction of information of L3 products.

P.3-4

Update of file naming conventions of L3 Standard Products

Table 3.1-12

for V07.
Addition of information of NOAA-20 and METOP-C.

Table 3.1-15

Update of URL information.

All
Appendix 4-1,

Deletion Appendix 4-1 and Appendix 5-1 and update ofAppendix 5-1,

Appendix 3-1

Appendix 3-1v

GPM Data Utilization Handbook

revision

date

VersionJan. 24th 2022

4.1

sectioncontent, reason

All,

Update of information for DPR specification.

P.2-2,
Table 2.1-2,
Table 2.2-1,
Table 3.2-1

VersionJuly 7th 2023

4.2

P.2-5, P3-31,

Addition of information of NOAA-21.

Table 2.1-3,
Table3.1-15

VersionMar 5th 2024

5.0

Preface,

Corrections due to GPM Core satellite performed two orbit

P.2-5, P.2-6,

boost maneuvers that raised its altitude

P.2-10, P.2-12,
P.3-2, P.3-33,
P.4-11, P.5-1,
P.5-3, P.5-5,
P.5-6, P.5-8,
P.5-9, P.5-11,
Table 2.1-2,
Table 2.2-1,
Table 2.2-2,
Table 2.2-3,
Table 3.1-3,
Table 3.1-4,
Table 3.2-1,
Appendix 2-1

Version
5.1

Mar 18th 2024

Table 2.1-3

Constellation satellite information update

Table 2.2-3

Typo correction

Preface,

Satellite altitude information update

P.2-1, P.2-10

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GPM Data Utilization Handbook

INTRODUCTION
The Global Precipitation Measurement (GPM) Core Satellite was launched by H-IIA Launch Vehicle
No.23 at 3:07 a.m. JST Friday, Feb. 28 from the Tanegashima Space Center.
This satellite has been developed as a joint project between JAXA and NASA and the Dualfrequency Precipitation Radar (DPR) carried on the satellite is the observation device developed by
JAXA with the National Institute of Information and Communication Technology (NICT).
GPM performs the observation of rain intensity and the distribution of Approx. 90 percent region ofwhole globe. And the data from GPM Core Satellite and the constellation satellite of GPM plan is
expected that it will play an integral role in elucidating global climate change and monitoring
environmental change.

1.1. Purpose
We introduce not only various information related to standard products and near-real-time products,
but also information related to GPM Core Satellite itself, as well as other related information about thesensors on the Satellite and the ground systems.

1.2. Scope
This document consists of five sections and appendices:
Section 1 : Describes the purpose and scope of the document and the overview of GPM mission;
Section 2 : Introduces the outline of GPM system, describes the details of specification of DPR
sensor and GMI sensor and also ground system related to GPM;
Section 3 : Describes the outline of data processing algorithm and data format of standard products
and near-real-time products provided by JAXA;
Section 4 : Describes the outline of data services related to standard products and near-real-time
products provided by JAXA Earth Observation Satellite Data Distribution System(GPortal);
Section 5 : Describes the outline of software tools to visualize or analyze GPM data.

1.3. Overview of GPM Project
The Global Precipitation Measurement Project (GPM) is follow-on and expansion of the tropicalrain observation satellite (TRMM) satellite, and an international cooperative mission to measure global
precipitation more accurately and frequently for elucidating changes in climate and water circulation
using one GPM core satellite with the Dual-frequency Precipitation Radar (DPR) and the GPM
Microwave Imager (GMI) onboard and constellation of several other satellites with a microwave
imager onboard. Figure 1.3-1 provides an overview of GPM project.

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GPM Data Utilization Handbook

Constellation satellites

Core Observatory(a microwave imager onboard)(DPR and GMI onboard)

Figure 1.3-1 Overview of GPM Project
Similar to a mission for water cycle variation observation under JAXA’s Earth Environmental
program, mission objectives of GPM are to continue and expand knowledge and outcomes obtainedby the TRMM satellite, and to achieve the following targets:(1) Highly accurate and frequent global precipitation observation for climate and water cyclechange(2) Data utilization method development through distribution of near real time global precipitation
maps(3) Development and demonstration of the improved precipitation retrieval method of the multimicrowave radiometers (including both imager and sounder) using DPR data
(4) Application demonstration for operational use, such as flood prediction, numerical weather
forecast, prevention of damage from a storm and flood; and(5) Demonstration of DPR technology, which will succeed and expand TRMM/PR technology, toachieve highly accurate precipitation observation.
The applications for which future growth is expected through GPM mission shows below.

(1) Utilization in Weather Forecasts
Satellite data is used commonly in weather forecasts. The Japan Meteorological Agency (JMA) has
been using satellite microwave brightness temperature data in its numerical weather prediction since2003, and has been introducing data from the Global Change Observation Mission - Water (GCOM-

1-2

GPM Data Utilization HandbookW) satellite since August 2013. This data contributes to improve the accuracy of weather forecasts,
and also achieves more accurate typhoon analyses. For example, errors with numerical weather
prediction have decreased by about 25% during the period from 2004 to 2012 through the introductionof satellite data and improvements in model schemes. For typhoon analysis, estimates of the positionof the typhoon's eye that is difficult to determine from geostationary satellites are improved by thepassive microwave imagers, as well as from improvements in the storm track forecasts. As for GPM
era, JMA is preparing for operational use of it in its system, and meteorological agencies in the othercountries plan to use it too.
Improvements in the accuracy of weather forecasts also directly contribute to weather information
services and society. Weather information is used in routine work for the service and retail industries,
traffics, agriculture, forestry and fisheries industries, and the infrastructure-related fields. Furthermore,
improvements in the storm track forecast accuracy of tropical cyclones will largely contribute toprotecting the human lives and property. It was estimated that the data from the Tropical Rainfall
Measuring Mission (TRMM) satellite contributes to protecting lives of 100–500 people per year in
the world (Adler, 2005). Recently, the Japan Weather Association has started to release regional
satellite images through cell-phone website using JAXA Global Rainfall Watch (GSMaP) and the
GCOM-W data.

(2) Utilization in Flood Predictions and River Managements
During 10-year from 1988 to 1997, two thirds of natural catastrophes worldwide were caused byfloods and storms (World Water Council, 2000). The GSMaP product, which was developed in JapanFor the GPM mission, provides an hourly global rainfall map four hour after observation. The flood
alert system and tool, which use the GSMaP as inputs, are developed on a trial basis by theInternational Centre for Water Hazard and Risk Managements (ICHARM), a UNESCO Category II
Centre and hosted by the Public Works Research Institute (PWRI), and the Infrastructure
Development Institute (IDI-JAPAN), the secretariat of International Flood Network (IFNet). The
GSMaP is expected to be used in operation in the GPM era. Since the satellite data is especiallyeffective in the regions that are lacking in ground observations, efforts toward utilizing satellite datain flood predictions and river managements are underway in many Asian countries through funding
from UNESCO, the Asian Development Bank, etc.

(3) Utilization in Global Change and Climate Variation Studies
Future projections of precipitation were reported by the Intergovernmental Panel on Climate Change(IPCC) Working Group I in September 2013 as a contribution to the Fifth Assessment Report that
“Extreme precipitation events over most of the mid-latitude land masses and over wet tropical regions
will very likely become more intense and more frequent by the end of this century, as global meansurface temperature increases.” The latest simulations by climate models indicate that changes in the
global water cycle in response to global warming, such as an increase in the contrast of precipitation
between wet and dry regions and between wet and dry seasons.
Current global climate models, however, still have uncertainty in projections in precipitation changes
in response to global warming. Information from the GPM mission, especially highly accurate threedimensional information of precipitation particles and systems derived from the Dual-frequency

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GPM Data Utilization Handbook

Precipitation Radar (DPR) will contribute in the validation of climate models and improvements in the
precipitation processes. Another important role of satellite observation is to monitor long term changes
in precipitation distribution, by combining various satellite and ground observation. To detect globalscale changes, global observations by satellites are essential.
Studies of precipitation system climatology have made substantial progress since the launch of the
TRMM satellite and the Precipitation Radar (PR). Diurnal cycles of rainfall over the tropical regions
were revealed by PR observations, as were the typical rainfall system of each region and statistics on
extreme rainfall events. Observations that lead to a significant increase in the frequency of recent
extreme rainfall events may be obtained by long term records, which will be carried on for more than
20 years through the TRMM to the GPM.

(4) Utilization in Water Cycle Studies
To assess the global water cycle quantitatively, observations of precipitation that is observable flux
quantity is essential. Precipitation observations in the mid-latitude whose rainy areas are brought by
extra tropical cyclones follow that in the tropics and subtropics, and are critical as a new challenge in
the GPM mission.
It is expected that improvements in temporal and spatial resolution in GPM precipitation
observations will contribute to the refinement of hydrological models. GPM data will quantify thewater cycle and its variations, and be a big step to identify natural and anthropogenic variations in thewater cycle. Studies to simulate rive runoff and use satellite global rainfall map as inputs to land models
are underway and at the evaluation stage for operational use in flood monitoring and water resource
management.

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GPM Data Utilization Handbook

GPM/TRMM SATELLITE SYSTEM
This chapter provides not only the overview of the GPM and TRMM spacecraft subsystems but the
specification of its onboard instruments such as DPR sensor and GMI sensor. In addition, this chapter
describes the outline of the ground systems related to GPM and TRMM operation.

2.1. Overview of the GPM Spacecraft
2.1.1. GPM Project
The Global Precipitation Measurement Project (GPM) is an international cooperative mission tomeasure global precipitation more accurately and frequently using one GPM core satellite with theDual-frequency Precipitation Radar (DPR) and the GPM Microwave Imager (GMI) onboard and othersub-satellites with either a microwave imager (imager/sounder) onboard. By cooperation with multiple
number of constellation satellites will enable global measurement of precipitation about every threehours. Figure 2.1-1 shows constellation satellites consists GPM Project.

Figure 2.1-1 GPM Constellation of Satellites
The GPM core satellite has been cooperatively developed by JAXA and NASA, and the DPR has
been jointly developed by JAXA in cooperation with NICT. And JAXA performs both developing
mission instruments as well as launch services with the H-IIA Rocket Vehicle at Tanegashima Space
Center and data processing/providing.
The constellation of satellites is feasible by international cooperation for the existing or future
microwave imager (imager/sounder) onboard project of which NASA, National Oceanic andAtmospheric Administration (NOAA), European Organization for the Exploitation of Meteorological
Satellites (EUMETSAT), Centre National D'Etudes Spatiales (CNES), and Indian Space Research

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GPM Data Utilization Handbook

Organization (ISRO), and so on. Here is the responsibility sharing between GPM Core Satellite andconstellation satellites of each international partner (space agency) below.
Table 2.1-1 Responsibility Sharing between GPM Core Observatory and Constellation Satellites
NASA

GPM Core
Satellite

Satellite bus
Instruments
DPR
GMI
LaunchTracking andControl
Data processing
Data distribution

Constellation satellites

JAXA

Note

X

Developed with NICTX

H-IIA Launch Vehicle

X

X
X
X
X
X
X
NASA (USA), NOAA (USA),
CNES (France)/ISRO (India),
EUMETSAT (EU), JAXA, etc.

2.1.2. Outline of GPM Core Satellite
GPM Core Satellite carries Dual-frequency Precipitation Radar (DPR) and a microwave radiometer.
Main purposes of the GPM are “Comprehension of horizontal and vertical structure of precipitation
systems”, “Acquisition of precipitation particles information” and “Improvement of accuracy of
precipitation by constellation satellites”.
GPM Core Satellite can observe the range from the south latitude about 65 degrees to the northlatitude about 65 degrees, and flies Non-Sun-synchronous Circular Orbit at about the 407 km altitude.
To keep the altitude, the Core Satellite does the orbit maintenance maneuver. The interval is about 710 days. In addition, asGPM Core satellite performed two orbit boost maneuvers on
Nov. 2023 that raised its altitude, the satellite altitude rose to approximately 442 km.
Overview of GPM Core Satellite is shown in Figure 2.1-2, Main Characteristics of GPM Core
Satellite are shown in Table 2.1-2 and the concept of precipitation observation by the GPM Core
Satellite (at about 407 km altitude) is shown in Figure 2.1-3.

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GPM Data Utilization Handbook

GPM Microwave Imager (GMI)

Dual-frequency Precipitation Radar (DPR)
Ku-band Radar (KuPR)
Dual-frequency Precipitation Radar (DPR)
Ka-band Radar (KaPR)

Solar array paddles

Figure 2.1-2 Overview Design of GPM Core Satellite
Table 2.1-2 Main Characteristics of GPM Core Satellite
Main Characteristics
Launcher
Launch date
Orbit
Altitude
Inclination
Semi-major axis
A/C Altitude Control Box
Orbit Eccentricity
Transmission path
Design life
Instruments

WeightDimensions

GPM Core Observatory
H-IIA Launch Vehicle No.23(from Tanegashima Space Center)February 27, 2014 (UTC)
Non-Sun-synchronous Circular Orbit
397–419 km (before Nov. 2023)
432–454 km (after Nov. 2023)
Approx. 65 degrees
Approx. 6776 km (before Nov. 2023)
Approx. 6811 km (after Nov. 2023)±1 km
0.00010
Via NASA/Tracking and Data Relay Satellite (TDRSS)
3 years and 2 months after the launch
Dual-frequency Precipitation Radar (DPR)・Ku Band Rader (KuPR)・Ka Band Rader (KaPR)
GPM Microwave Imager (GMI)
Approx. 3850 kg
13.0 m × 6.5 m × 5.0 m

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GPM Data Utilization Handbook

Movingdirection
Altitude
407km

Figure 2.1-3 Concept of Precipitation Observation by the GPM Core Observatory
The main role of Core Satellite is to work as a calibrator for all observation data by simultaneous
measurements of DPR and GMI instruments and to improve precipitation observation accuracy of
microwave radiometer including constellation satellites.

2.1.3. Outline of GPM Constellation Satellites
Only one satellite for the low-earth-orbit satellite like TRMM lowers the frequency of theobservation. In the GPM mission, it cooperates with other satellites to overcome this weak point, andto achieve the frequent observation. The existing satellites carrying microwave radiometer or the
microwave sounder around year 2014 configure GPM constellation satellites. The list of constellation
satellites is shown in Table 2.1-3.
Table 2.1-3 List of Constellation Satellites
SensorSatellite

TRMM Microwave Imager(TMI)

Tropical Rainfall
Measuring Mission(TRMM)
Defense Meteorological
Satellite Program (DMSP)
seriesDefense Meteorological
Satellite Program (DMSP)
seriesSpecial Sensor Microwave
Imager (SSMI)
Special Sensor Microwave
Imager/Sounder (SSMIS)

2-4

PeriodOrganization

1997–2015

NASA

F-15：1999– in operation

DoD

F-16：2003– in operation
F-17：2006– in operation
F-18：2009– in operation
F-19：2014–2016

DoD

GPM Data Utilization Handbook

SensorAdvanced Microwave
Scanning Radiometer2(AMSR2)
Microwave Analysis andDetection of Rain andAtmospheric Systems(MADRAS)
Sondeur Atmospherique duProfil d'Humidite
Intertropicale parRadiometrie (SAPHIR)
Microwave Humidity
Sounder (MHS)

Satellite
Global Change
Observation Mission –Water (GCOM-W)
Megha-Tropiques

National Oceanic andAtmospheric
Administration (NOAA)
series

2011–2013

CNES/ISRONOAA-18：2005–2018
NOAA-19：2009– in operation

NOAA

NOAA-18：2005–2018
NOAA-19：2009– in operation
MetOp series

Metop-A：2006–2021
Metop-B：2012– in operation
Metop-C：2018– not determined

AMSU-A

Advanced Technology
Microwave Sounder(ATMS)

Organization
JAXA

2011– in operation

Advanced Microwave
Sounding Unit-A(AMSU-A)
MHS

Period
2012– in operation

EUMETSAT

Metop-A：2006–2021
Metop-B：2012– in operation
Metop-C：2018– in operation
NOAA-NASA Joint Polar
Satellite System (JPSS)

2-5

Suomi NPP
：2011– in operation
NOAA-20：2017– in operation
NOAA-21：2023– in operation

NASA/NOAAGPM Data Utilization Handbook

2.2. Outline of GPM Mission Critical Devices
2.2.1. The Dual-frequency Precipitation Radar (DPR)
The DPR has two different frequencies to measure the three-dimensional structure of precipitation,and is capable of observing snowfall from space for the first time, in addition to observing both strong
and weak rainfall. The DPR’s observations will provide global precipitation dataset including weak
rainfall by extra tropical cyclones in mid-to-high latitudes, in addition to carrying on the archive of
long-term rainfall dataset in the tropics and the subtropics by PR. Furthermore, through its highresolution and highly accurate observations, DPR will play a role of the reference standard for the
microwave radiometers carrying on the Constellation Satellites who join the GPM mission, throughthe GPM Microwave Imager on board the same platform. The swaths of DPR instrument are about 125
and 245 km (78 and 152 mile) for a Ka-band precipitation radar (KaPR) (about 245 km after May 21,2018) and a Ku-band precipitation radar (KuPR) respectively. In addition, simultaneous measurements
are done at the overlapping of Ka/Ku-bands of the DPR. The GMI instrument is a conical-scanning
multi-channel microwave radiometer covering a swath of 904 km (565 miles).
The appearance diagram of DPR is shown in Figure 2.2-1 and the main characteristics of DPR are
shown in Table 2.2-1.

Ka-band Radar (KaPR)

Ku-band Radar (KuPR)

Figure 2.2-1 Appearance of DPR
Table 2.2-1 Main Characteristics of DPR (Specification)
Main Characteristics

KuPR

KaPR

Radar Type
Antenna
Frequency
Peak Transmit Power
Range Resolution
Pulse Width

Ku-band
13.597, 13.603 GHz> 1000 W≤ 250 m1.67 microseconds

2-6

Active Phased Array Radar
Slotted Waveguide Antenna
Ka-band35.547, 35.553 GHz> 140 W
≤ 250 m / ≤ 500 m
1.67 microseconds /GPM Data Utilization Handbook

Main Characteristics

KuPR

Horizontal Resolution
Beam WidthBand Width
Beam Number

KaPR
3.34 microseconds
5.04 +/- 0.14 km (at nadir)【5.48km ± 0.16 km (at nadir) (after Nov. 8th 2023)】

0.71 degrees +/- 0.02 degrees (at nadir)
14 MHz49
49
Before May 21, 2018:
25 in matched beams
24 in interlaced scans
After May 21, 2018:
25 in matched beams
24 in matched beams with high sensitivity
128 Solid State Amplifiers
1012.0 W
146.5 W
variable≥ Approx. 245 km≥ Approx. 125 km≥ Approx. 245 km after May 21, 2018
【Approx. 278 km (after Nov. 8th 2023)】

Transmitter
Peak Transmit Power
Pulse Repetition Frequency (PRF)
Swath Width
Scan Interval
Observable Range

0.7 sec
Up to 19 km
Specification:0.5 mm/hr

Minimum Detectable Rain Rate

Theoretical value:0.30 mm/hr【0.33 mm/hr(after Nov. 8th 2023)】

Receiver power accuracy

Dimensions

Matched beamSpecification: 0.2 mm/hr

Specification:0.2 mm/hr

Theoretical value:0.16 mm/hr【0.19 mm/hr

Theoretical value:0.38 mm/hr【0.42 mm/hr(after Nov. 8th 2023)】(after Nov. 8th 2023)】+/- 1dB< 1000 m【< 1090 m (after Nov. 8th 2023)】

Beam-matching Error
Design life
Data Rate
Mass
Power Consumption

High sensibility beam

3 years and 2 months after the launch< 109 kbps
< 81 kbps< 415 kg
< 336 kg
< 446 W orbit average< 344 W orbit average
Approx. 2.6 m × 2.4 m ×
Approx. 1.3 m × 1.5 m × 0.8 m
0.7 m(1) Observation Overview
The DPR is composed of two radars; a Ku-band Precipitation Radar (KuPR) and a Ka-band
Precipitation Radar (KaPR). The KaPR instrument aims at sensitive observations, and can detect weak
rainfall and snowfall that cannot be measured by the KuPR. Since the KuPR instrument can detectheavier rainfall, simultaneous observations by the KaPR and KuPR will enable accurate measurements
of precipitation from heavy rainfall in the tropics to weak snowfall in high-latitudes.

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In general, strength of precipitation echoes is affected by attenuation due to precipitation on thosefrequencies, but the amount of attenuation depends on the frequency and the size of raindrops. The
KuPR and KaPR, therefore, match their radar beam positions and transmission pulse timings of eachother to estimate a size of a raindrop (Raindrop Size Distribution, DSD) by calculating the differencein precipitation attenuations. The Observation Image Diagram of DPR is shown in Figure 2.2-2.

Ka-banddual-frequency

Ku-bandtransmission beamReflection echoIcecrystalssnow

Meltinglayer
Rain

Figure 2.2-2 Observation Image Diagram of DPR(2) Operational Mode
The usual DPR operation mode is "Observation mode". However, other operation modes exist in
DPR, and it is necessary to note the handling of data enough for those operation modes.
The DPR Operation Modes are shown in Table 2.2-2.
Table 2.2-2 DPR Operation Modes
Operational
Mode
Observation
Mode

Description
During this mode, the KuPR and KaPR
instruments perform normal rain echomeasurements with a ±17.04 degrees
scanning capability (49 beams) for

2-8

Frequency (*)

Note for data utilization

usual

DPR L1 product withmodes except“Observation Mode” isnot able to use forGPM Data Utilization Handbook

Operational
Mode

External
Calibration
Mode
Internal
Calibration
Mode

SSPA Analysis
Mode

LNA Analysis
Mode

Health-CheckMode

Description

Frequency (*)

KuPR and with a ±8.52 degrees (±17.04 degrees after May 21th, 2018)
scanning capability (49 beams) for
KaPR.
During this mode, DPR calibration andbeam matching measurements between
KuPR and KaPR are performed by
Active radio calibrator (ARC) on the
ground.
During this mode, DPR receivercalibration is performed by using aloopback RF signal of FCIF.
The receiving beam is fixed to the scanangle bin specified by commands, and apulse is transmitted with one SSPA
element one by one. The reflection echo
from the sea surface is observed and it
is confirmed that each element of SSPA
has amplified the signal correctly.
The transmission beam is fixed to thescan angle bin specified by commands,
and a regulated pulse is transmitted. The
reflection echo from the sea surface isreceived one by one in LNA. It is
confirmed that each element of LNA
has amplified the signal correctly.
Health-Check of internal function of
SCDP is performed.

8 times / year
(7 minutes /time)
once / week
(2 minutes or 35
minutes / time)

Note for data utilization
physical quantities
calculation like rain rate.
It is necessary to check“operational mode” andto process “Observation
Mode” data only.
The missing value isstored in the DPR L2
product which mode is not"Observation Mode".

4 times / year
(5 minutes /time)

4 times / year
(5 minutes /times or 92
minutes / times)
when DPR
operational modetransition occurs

This mode is used for re-loading phasewhen DPR
code and VPRF data, changing timing
operational modeStand-by Mode
offset between KuPR and KaPR, andtransition occurs
dumping current parameters.
This shall be the mode which the DPR
is only provided DPR survival heater
when anomaly of
power from the Spacecraft. The DPR isSpacecraft or
Safety Modenot provided DPR instrument power for
DPR
observation from the Spacecraft in thismode.
(*) The frequency shown here is the one for the nominal operation period.

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GPM Data Utilization Handbook

2.2.2. The GPM Microwave Imager (GMI)The Global Precipitation Measurement (GPM) Microwave Imager (GMI) instrument is a multichannel, conical- scanning, microwave radiometer serving an essential role in the near-global-coverageand frequent-revisit-time requirements of GPM.
The GMI is characterized by thirteen microwave channels ranging in frequency from 10 GHz to 183
GHz. In addition to carrying channels similar to those on the Tropical Rainfall Measuring Mission(TRMM) Microwave Imager (TMI), the GMI carries four high frequency, millimeter-wave, channels
about 166 GHz and 183 GHz. With a 1.2 m diameter antenna, the GMI will provide significantly
improved spatial resolution over TMI.
The off-nadir-angle defining the cone swept out by the GMI is set at 48.5 degrees which represents
an earth-incidence-angle of 52.8 degrees. To maintain similar geometry with the predecessor TMI
instrument, the-earth-incidence angle of GMI was chosen identical to that of the TMI. Rotating at 32
rotations per minute, the GMI will gather microwave radiometric brightness measurements over a 140
degrees sector centered about the spacecraft ground track vector. The remaining angular sector is used
for performing calibration; i.e. observation of cold space as well as observation of a hot calibration
target. The 140 degrees GMI swath represents a swath of 904 km (562 miles) on the Earth's surface.
Only the central portions of the GMI swath will overlap the DPR swaths (and with approximately
67 second duration between measurements due to the geometry and spacecraft motion). These
measurements within the overlapped swaths are important for improving precipitation retrievals, andin particular, the radiometer-based retrievals.
The appearance diagram of GMI is shown in Figure 2.2-3 and the main characteristics of GMI are
shown in Table 2.2-3.
In November 2023, the satellite performed two orbit boost maneuvers that raised its altitude toapproximately 442km. As a result, the off-nadir angle of GMI was 49.5°, which corresponds to an
incidence angle of 53.2°. The observation scanning angle remained at 140° (±70°), so the scanning
width was expanded to approximately 1015 km.
Figure 2.2-4 shows an outline of GMI observation before and after raised the satellite altitude.

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GPM Data Utilization Handbook

Figure 2.2-3 Appearance of GMI
Table 2.2-3 Main Characteristics of GMI
Main Characteristics
Frequency

Horizontal Resolution
Swath Width

GMI
10.65 GHz (V/H), 18.7 GHz (V/H),
23.8 GHz (V), 36.5 GHz (V/H),
89.0 GHz(V/H), 165.5 GHz (V/H),
183.31 ± 3 GHz (V), 183.31 ± 8 GHz (V)
6 to 26 km【6 to 28 km (after Nov. 8th 2023)】
904 km【1015 km (after Nov. 8th 2023)】

Scan Interval
Design life
Data Rate
WeightPower Consumption
Dimensions (diameter ofantenna)
Off-Nadir Angle

1.875 sec
3 years and 2 months< 25 kbps< 153 kg< 141 W
1.2 m
48.5 degree (Incidence Angle:52.8 degree)【49.5 degree (Incidence Angle:53.2 degree)(after Nov. 8th 2023)】

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GPM Data Utilization Handbook

Figure 2.2-4 Outline of GMI observation before and after raised the satellite altitude

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GPM Data Utilization Handbook

2.3. Overview of the TRMM Spacecraft
2.3.1. Outline of TRMM Satellite
TRMM mainly observes rain structure, rate and distribution in tropical and subtropical regions, thedata plays an important role for understanding mechanisms of global climate change and monitoring
environmental variation.
The TRMM observatory includes five science instruments, namely the Precipitation Radar (PR), theTRMM Microwave Imager (TMI), the Visible and Infrared Scanner (VIRS), the Clouds and the Earth's
Radiant Energy System (CERES), and the Lightning Imaging Sensor (LIS).
TRMM has three instruments (PR, TMI, and VlRS) in its rainfall measurement package, to obtain
tropical and subtropical rainfall measurements, rain profiles, and brightness temperature. TRMM has
the only passive microwave instrument (TMI) in an inclined orbit and the only rain radar (PR) in space.
The three rain instruments are providing the most complete rain data set (to date) in order to generate
climate models and perform severe storm studies. The two additional instruments flown on-board
TRMM are the CERES and LIS. CERES and LIS are flown on board TRMM as instruments ofopportunity for the Earth Observation System Program. The CERES instrument measures the Earth's
radiation budget, and the LIS instrument investigates the global distribution of lightning.
Overview of TRMM Satellite is shown in Figure 2.3-1, Main Characteristics of TRMM Satellite areshown in Table 2.3-1 and the TRMM operation history is shown in Table 2.3-2.

Figure 2.3-1 Overview of TRMM Satellite
Table 2.3-1 Main Characteristics of TRMM Satellite
Characteristics
Launcher
Launch date (JST)
Orbit
Altitude
Inclination

TRMM Satellite
H-II Launch Vehicle No.6
November 28, 1997
Non-Sun-synchronous Circular Orbit
Approx. 350 km (Approx. 402.5 km*)
Approx. 35 degrees

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GPM Data Utilization Handbook

Characteristics
Data transmission
Design life
Mission instrument

WeightShape

TRMM Satellite
Via TDRS
32Kbps (Real Time), 2Mbps (Play Back)3 years and 2 months
Precipitation Radar (PR)TRMM Microwave Imager (TMl)
Visible and Infrared Scanner (VIRS)
Clouds and the Earth’s Radiant Energy System(CERES)Lightning Imaging Sensor (LIS)
Approx. 3524 kg
At lift-off: 5.1 m (length), 3.7 m (diameter)
In orbit: 5.1 m (length), 14.6 m (in paddle direction)*: Post orbit boost (August 25, 2001)

Table 2.3-2 TRMM operation history
Date

Event

1997/11

Launch by the H-II Launch Vehicle No.6 from
Tanegashima Space Center (28th)
Publication for TRMM products L1 version 4
Publication for TRMM products L2-3 version 4
Instruments powered off due to Leonid Storm (18th–19th)
Instruments powered off in Sun Acquisition mode (3rd–
6th)
Publication for TRMM products version 5
Instruments powered off due to Leonid Storm (17th–18th)
Instrument powered off in Low Power mode (17th–22nd)
Instruments powered off due to Leonid Storm (18th)
Suspension of CERES operation.
TRMM boost (350 km–402.5 km). (7th–24th)
Instruments powered off due to Leonid Storm (18th–19th)
Publication for TRMM products version 6
Instruments powered off due to Leonid Storm (18th–19th)
Instruments powered off due to PR anomaly (29th–June
18th)
Publication for TRMM products version 7
TRMM boost (402.5 km–350 km). (7th–Feb 12th 2015)
TRMM satellite re-entered the atmosphere (16th)

1998/06
1998/09
1998/11
1999/01
1999/11
1999/11
2000/09
2000/11
2001/05
2001/08
2001/11
2002/06
2002/11
2009/05
2011/07
2014/10
2015/06

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GPM Data Utilization Handbook

2.4. Outline of TRMM Mission Critical Devices
2.4.1. Precipitation Radar (PR)When properly combined with TMI measurements, the PR data is instrumental in obtaining theheight profile of the precipitation content, from which the profile of latent heat release from the Earthcan be estimated. The rain rate is estimated from the radar reflectivity factor when the rain rate is small
by applying conventional algorithms used for ground-based radar. For large rain rates, a rain
attenuation correction is made using the total-path attenuation of land or sea surface echoes.
The appearance diagram of PR is shown in Figure 2.4-1 and the main characteristics of PR are shownin Table 2.4-1.

Figure 2.4-1 Appearance of PR
Table 2.4-1 Main Characteristics of PR
Main Characteristics

PR

Radar Type

Active Phased Array Radar
13.796 GHz & 13.802 GHz(Two-channel frequency agility)
250 m
1.6 μs4.34 km ± 0.12 km (at nadir)*
0.71 deg. × 0.71 deg.
~215 km*
From surface to height ≥ 15 km*
S/N per pulse ≥ 0 dB for 0.5 mm/h rain at rain top*
93.5 kbps
465 kg213 W

Frequency
Range Resolution
Pulse Width
Horizontal Resolution
Beam Width
Swath Width
Observable Range
Sensitivity
Data Rate
WeightPower*: Post orbit boost (August 25, 2001)(1) Operational Mode
The usual PR operation mode is "Observation". However, other operation modes exist in PR, and it

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GPM Data Utilization Handbook

is necessary to note the handling of data enough for those operation modes.
The PR Operation Modes are shown in Table 2.4-2.
Table 2.4-2 PR Operational Modes
PR MODE

MODE DESCRIPTION

Observation

This will be the normal operating mode of the instrument. During this mode, the PR instrument
performs normal rain echo measurements with a ± 17˚ scanning range.

External
Calibration

This mode will provide an on-orbit calibration of the PR instrument by the Active Radar Calibrator(ARC) on the ground. Limited scan or Fixed beam submodes may be used in either the spacecraft
nominal configuration or the 90˚ yaw configuration.
Limited scan - scanning for 7 beam directions centered at a selected angle bin.
Fixed beam - Beam is fixed to a selected angle bin. No scanning is performed.

InternalThis mode will provide an on-orbit calibration about the input-output characteristics of LOGAMP

Calibration

with internal loop signal. During this mode, no RF signal is radiated from the antenna and scienceobservation will not occur.

HealthThis mode is for checking RAMs and ROMs used in the System Control Data Processing (SCDP)

Check

component. By electrical power turn-on, PR moves from Safety Mode to this mode.

LNA

This mode is used to check whether each LNA is alive or not. During this mode, no science

Analysis

observation will occur.

Stand-By

This mode is for checking the phase code stored in the SCDP. Also, this mode shall be selected totemporarily stop the RF radiation. During this mode, the PR instrument is ON but is not initiating

Safetyany RF transmissions.
This mode will be used when the TRMM observatory is in any of the following modes of operation:- Launch Mode
- Initial Orbit Acquisition Mode
- Safe-Hold/Low Power Mode
When Safe-hold/Low Power signal is received, the PR instrument will be internally commanded
to this mode, prior to the autonomous removal of the NEB power supply. During this mode, the PR
instrument is OFF with the exception of the survival heaters.

2.4.2. TRMM Microwave Imager (TMI)The TRMM Microwave Imager (TMI) is a Multi-channel dual-polarized passive microwave
radiometer. TMI utilizes nine channels with operating frequencies of l0.65 GHz, 19.35 GHz, 21.3 GHz,
37 GHz, and 85.5 GHz. The TMI instrument provides data related to the rainfall rates over the oceans,
but less reliable data over land, where non-homogeneous surface emissions make interpretationdifficult. The TMI instrument is similar to the SSM/I instrument currently in orbit on the Defense
Meteorological Satellite Program spacecraft. The TMI data combined with the data from the PR and
VIRS also utilized for deriving precipitation profiles.
The TMI instrument has a single operational mode and no commendable redundancy. Accordingly,
command procedures are minimal and focus on power and heater control. TMI essentially has twomodes, OFF and ON. Two external calibrators on the stationary shaft are used to perform calibrations
during each instrument rotation (scan). The instrument spins at a rate of 31.6 RPM. Each scan begins
with 130˚ of scene data, followed by a cold reference measurement and then a hot load reference
measurement. These reference measurements, along with the known temperatures of the calibrationloads, serve to calibrate the scan.

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GPM Data Utilization Handbook

The appearance diagram of TMI is shown in Figure 2.4-2 and the main characteristics of TMI are
shown in Table 2.4-3.

Figure 2.4-2 Appearance of TMI
Table 2.4-3 Main Characteristics of TMI
Main Characteristics

TMI

Observation Frequency
Horizontal Resolution
Swath Width
Data Rate
WeightPower

10.65, 19.35, 21.3, 37 and 85.5 GHz
6 - 50 km*~ 760 km*
8.8 kbps
50 kg
39 W

*: Post orbit boost (August 25, 2001)

2.4.3. Visible and Infrared Scanner （VIRS）
The VIRS instrument is a cross-track scanning radiometer, which measures scene radiance in fivespectral bands, operating in the visible through infrared spectral regions. VIRS is similar to instruments
flown on other NASA and NOAA meteorological satellites. Comparison of the microwave data with
VIRS visible and infrared data is expected to provide the means whereby precipitation can be estimatedmore accurately than by visible and infrared data alone. The VIRS instrument serves as a backgroundimager and provides the cloud context within which the passive microwave and radar observations are
made. Data from the VIRS instrument is used in rain estimation algorithms based primarily on thepassive and active microwave sensors.
The appearance diagram of VIRS is shown in Figure 2.4-3 and the main characteristics of VIRS are
shown in Table 2.4-4.

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GPM Data Utilization Handbook

Figure 2.4-3 Appearance of VIRS
Table 2.4-4 Main Characteristics of VIRS
Main Characteristics

VIRS

Observation Band
Swath Width

0.63, 1.61, 3.75, 10.80 & 12.00 µm
Scan angle ± 45 degrees, 720 km* atground50 kbps (Daytime)
49 kg
53 W

Data Rate
WeightPower*: Post orbit boost (August 25, 2001)

2.4.4. Clouds and the Earth's Radiant Energy System （CERES）
The CERES experiment will help reduce one of the major uncertainties in predicting long-termchanges in the Earth's climate. Radiant fluxes at the top of the Earth's atmosphere (TOA) were
measured by the Earth Radiation Budget Experiment (ERBE), not merely as an undifferentiated field,
but with reasonable separation between fluxes originating from clear and cloudy atmospheres. It wasalso discovered from ERBE that clouds have a greater effect on the TOA fluxes than was previously
believed, but details of the process are not yet fully understood. The CERES experiment will attempt
to provide a better understanding of how different cloud processes, such as convective activity andboundary-layer meteorology, affect the TOA fluxes. This understanding will help determine theradiative flux divergence, which enters directly into physically based, extended-range weather andclimate forecasting. CERES will also provide information to determine the surface radiation budget,which is important in atmospheric energetics, studies of biological productivity, and air-sea energy
transfer.
Since September 1998, however, CERES operated intermittently to acquire science data for only
campaign purpose, because an anomaly occurred on the power source of data collection system (DAA)of CERES in August 1998. Moreover, CERES operation was completely terminated since May 29
2001.
The appearance diagram of CERES is shown in Figure 2.4-4 and the main characteristics of CERES
are shown in Table 2.4-5.

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GPM Data Utilization Handbook

Figure 2.4-4 Appearance of CERES
Table 2.4-5 Main Characteristics of CERESMain Characteristics
Observation Band
Horizontal Resolution
Swath Width
Data Rate
WeightPower

CERES
0.3 – 5 μm (short Wave Channel)
8 – 12 μm (Long Wave Channel)
0.3 ~> 50 μm (Total Wave Channel)
10 km (nadir)
Scan Angle: ± 82 deg.
8.5 kbps
45.5 kg
47 W

2.4.5. Lightning Imaging Sensor （LIS）
The LIS is an optical staring telescope and filter imaging system that acquires and investigates the
distribution and variability of both intracloud and cloud-to-ground lightning over the Earth. The LIS
data also is used with PR, TMI and VIRS data to investigate the correlation of the global incidence oflightning with rainfall and other storm properties. The data from the LIS instrument can be correlated
to the global rates, amounts, and distribution of precipitation, and to the release and transport of latentheat. LIS is a single string instrument with multiple single points of failure. The LIS instrument was
powered ON during the initial instrument activation, and remains powered in that configuration for theduration of the mission (barring any unforeseen anomalous conditions).
The appearance diagram of LIS is shown in Figure 2.4-5 and the main characteristics of LIS are
shown in Table 2.4-6.

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GPM Data Utilization Handbook

Figure 2.4-5 Appearance of LIS
Table 2.4-6 Appearance of LIS
Main Characteristics

LIS

Observation Band

0.777655 μm

Horizontal Resolution

4 km (nadir)*Swath Width~ 600 km*

Data Rate

Ave. 6 kbps

Weight

18 kg

Power

42 W

*: Post orbit boost (August 25, 2001)

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GPM Data Utilization Handbook

2.5. Outline of ground system
2.5.1. GPM Ground System and data flow
GPM Ground System and its major facilities are shown in Figure 2.5-1.
Mission Operation Center (MOC) that exists in Goddard Space Flight Center (GSFC) of NASA
provides all facilities necessary to support spacecraft operations. It includes a command unlinking anda telemetry archival via Tracking and Data Relay Satellite (TDRSS). TDRSS consists of someconstellation satellites and can downlink approximately at all the time. Return/forward service data
rates are variable depending on the selection of Single Service Access (SSA) or Multi-Access (MA)
service utilization. For GPM operation, either MA (a phased array antenna) or SSA (a high-gain
antenna) service is applied to receive all telemetry data which are packed into 5-minute duration fileby the GPM core spacecraft. GMI science telemetry data, GMI HK telemetry data and spacecraft HK
telemetry data can be downlinked approximately at all the time via MA. On the other hand, DPR
telemetry data can be downlinked 2-3 times per one orbit via SSA because DPR data file size is larger
than GMI data file size. And for short or intermittent telemetry data outages resulting in the loss of filefragments, CCSDS File Delivery Protocol (CFDP) is used to automatically recover the telemetry data.
The received telemetry data is sent to the Precipitation Processing System (PPS) of NASA immediately
via MOC. After that, they are transmitted from PPS to JAXA GPM ground system in Tsukuba Space
Center (TKSC). An international dedicated line is used for this transmission to increase reliability.
Some microwave radiometer/sounder observation data (L1) are ingested by NASA and JAXA
ground system from Constellation Satellite Data Distribution Organizations. And environment
auxiliary data and IR data are collected from the Japan Meteorological Agency (JMA) and National
Oceanic and Atmospheric Administration (NOAA) etc. GPM products are generated using them andprovided to users.
JAXA GPM ground system consists of GPM/DPR mission operation system (GPM/MOS), Earth
Observation Satellite Data Distribution System (G-Portal) and JAXA Earth Observation ResearchCenter (EORC). In addition, GPM/MOS consists of the GPM/DPR Data Processing System (DPS) andthe Earth Observation Satellite Mission External Interface Gateway (E-XING). DPS receives DPR
science/HK telemetry data from NASA/PPS and GMI products and some microwave
radiometer/sounder observation data by constellation satellites and ancillary data via E-XING. DPS
conducts near-real-time (NRT) products processing immediately and conducts high-level processingof GPM standard products. These products are stored to E-XING and provide to G-Portal. The
registered user (researcher etc.) can search and obtain the GPM product from G-Portal. These datatransmission, reception, processing, archive, and distribution is automatically operated.

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GPM Data Utilization Handbook

Mission data

Mission data

GPM Core Observatory command

command
TDRSS(Tracking and Data Relay Satellite System)

WSC(White Sands ground station)
Mission data

NASA/MOC(Mission Operation Center)
ASD

Microwave radiometer
Constellation satellites
data distribution agencies

L1 data

GCOM-W
Mission Operation SystemAMSR2 L1

Japan Meteorological Agency

GANAL、FCST

CommandrequestTelemetryNASA facilities
JAXA facilities
External
Organizationand facilities

Operation
requestGPM products
NASA/PPS
Users(Precipitation Processing System)
DPR L1DPR APID Sorted Data, Orbit data, Ancillary data, IR
data, Gauge-based analysis data, GMI L1 to L3,
DPR operation request
DPR/GMI combined, Constellation satellites
microwave radiometer L1

GPM/DPR mission operation system(GPM/MOS)
Earth Observation Satellite Mission
External Interface Gateway (E-XING)

GMI/Constellation satellites
Standard and nearProductmicrowave radiometer L1, DPR L2, realtime product, Catalog
requestDPR/GPM combined, GSMaP
information, Browse
image
JAXA Earth Observation Satellite
ICHARM/IDI
Data Distribution System
Near(G-Portal)
realtime
Web
FTP
product

GPM/DPR Data
Processing Subsystem(DPS)Standard and near-realtime product, Catalog
information, Browse image, DPR operation
requestInterim data, Ancillary data, Standard andnear-realtime product, HK monitoring
data, Evaluation report for specificoperation mode
Calibration
coefficient,
GPM/DPR
Processing
Data Analysis System
software, Test data

Users

Figure 2.5-1 GPM Ground System

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GPM Data Utilization Handbook

GPM PRODUCTThis chapter describes outlines of data processing algorithm and data format of standard products
and near-real-time products provided by JAXA.

3.1. Outline of the Products
3.1.1. Scene Definitions(1) Scene of Level 1 and Level 2 Products
A scene of Level 1 and Level 2 DPR products is defined as data for an orbit with the southernmost point of
the Earth as the start point without overlap. Figure 3.1-1 shows an image of the scene definition of KuPR and
KaPR.
A near-real-time (NRT) GMI product’s file is generated by the receiving data of 5 minutes from the satellite.
A near-real-time DPR and DPR/GMI COMB product’s files are generated by the receiving data of 30 minutes
from the satellite.

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GPM Data Utilization Handbook

End point of a scene

Start point of a scene

Figure 3.1-1 Image of Scene Definition
The number of angle bin within one scan is 52 (0 to 51); 49 of them (1 to 49) are actually used for observation
by transmitting radio wave.
Figure 3.1-2 shown below is an outline of normal observation before KaPR scan pattern change. The swathof KuPR is about 245 km wide and that of KaPR is about 125 km wide.
In Ku/Ka/DPR L2 products, the names of scan are used as noted below;“FS” = Full scan, corresponding to the blue footprint (49 angle bin) in Figure 3.1-2.
“MS” = Matched beam scan, corresponding to the yellow footprint (25 angle bin) in Figure 3.1-2.
“HS” = High sensibility beam scan, corresponding to the red footprint (24 angle bin) in Figure 3.1-2.
On May 21, 2018, JAXA and NASA changed the scanning pattern of the KaPR. Figure 3.1-3 shown below
is an outline of normal observation after KaPR scan pattern change. KaPR High-Sensitivity (KaHS) beams
shown as red circles in Figure 3.1-2 scan in the inner swath before May 21 2018, but now they scan in theouter swath and match with KuPR’s beams.
Furthermore, because GPM Core satellite performed two orbit boost maneuvers that raised its altitude on
November 2023, the observation width of both KuPR and KaPR have become approximately 278 km.

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GPM Data Utilization Handbook

Figure 3.1-2 The Outline of KuPR and KaPR Under Normal Observation(Before KaPR scan pattern change)

Figure 3.1-3 The Outline of KuPR and KaPR Under Normal Observation(After KaPR scan pattern change)

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GPM Data Utilization Handbook(2) Scene of Level 3 Products
The following table shows a scene definition for GPM Level 3 products. The data format of the products
shown in Table 3.1-1 is gridded by using the scene coverage, respectively. However, the grid size and thescene coverage (the range of latitude) are different, respectively.
Table 3.1-1 Scene Definitions for Level 3 Products
Product
GPM DPR L3
Precipitation

GPM DPR L3
Spectral Latent
Heating (SLH)

GPM GMI L3
Precipitation
GPM DPR/GMI
Comb L3
Precipitation

GPM DPR/GMI
Comb L3
Convective
Stratiform Heating
(CSH)
GSMaP
Precipitation

Temporal Resolution and Grid Size
Standard Product- Daily (Text format)
Resolution: 0.1° × 0.1°
- Daily (HDF format)
Resolution: 0.25° × 0.25°- Daily (GeoTIFF format)
Resolution: 0.25° × 0.25°- Monthly (HDF format)
Resolution: 0.25° × 0.25°, 5° × 5°
- Monthly (GeoTIFF format)
Resolution: 0.25° × 0.25°
Standard Product- Gridded Orbital
Resolution: 0.5° × 0.5°
- Monthly
Resolution: 0.5° × 0.5°
Standard Product- Monthly
Resolution: 0.25° × 0.25°
Standard Product- Monthly
Resolution: 0.25° × 0.25° & 5° × 5°

Standard Product- Gridded Orbital
Resolution: 0.25° × 0.25°- Monthly
Resolution: 0.25° × 0.25°
Standard Product- Hourly (Text format)
Resolution: 0.1° × 0.1°
- Hourly (HDF format)
Resolution: 0.1° × 0.1°
- Hourly (GeoTIFF format)

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Scene Coverage(1) Resolution=0.1, 0.25°:
Products covering: 67°S to 67°N,
180°W to 180°E(2) Resolution=5°:
Products covering: 70°S to 70°N,
180°W to 180°E

Products covering: 67°S to 67°N,
180°W to 180°E

Products covering: 90°S to 90°N,
180°W to 180°E(1) Resolution=0.25°:
Products covering: 67°S to 67°N,
180°W to 180°E(2) Resolution=5°:
Products covering: 70°S to 70°N,
180°W to 180°E
Products covering: 67°S to 67°N,
180°W to 180°E

Products covering 90°S to 90°N,
180°W to 180°E

GPM Data Utilization Handbook

Product

TRMM PR/TMI
Comb L3
Precipitation

Temporal Resolution and Grid Size
Resolution: 0.1° × 0.1°
- Monthly (HDF format)
Resolution: 0.1°× 0.1°
- Monthly (GeoTIFF format)
Resolution: 0.1°× 0.1°
- Hourly (netCDF format)
Resolution: 0.1° × 0.1°
- Monthly (netCDF format)
Resolution: 0.1°× 0.1°
Near-Real-Time Product- Hourly (Text format)
Resolution: 0.1° × 0.1°
- Hourly (HDF format)
Resolution: 0.1° × 0.1°
Standard Product- Daily (Text format)
Resolution: 0.1° × 0.1°
- Daily (HDF format)
Resolution: 0.25° × 0.25°- Monthly (HDF format)
Resolution: 0.25° × 0.25°, 5° × 5°
Standard Product- Gridded Orbital
Resolution: 0.5° × 0.5°
- Monthly
Resolution: 0.5° × 0.5°
Standard Product- Monthly
Resolution: 0.25° × 0.25°
Standard Product- Monthly
Resolution: 0.25° × 0.25° & 5° × 5°

TRMM PR/TMI
Comb L3
Convective
Stratiform Heating(CSHT)

Standard Product- Gridded Orbital
Resolution: 0.25° × 0.25°- Monthly
Resolution: 0.25° × 0.25°

TRMM PR L3
Precipitation

TRMM PR L3
Spectral Latent
Heating (SLHT)

TRMM TMI L3
Precipitation

Scene Coverage

Products covering 90°S to 90°N,
180°W to 180°E(1) Resolution=0.1, 0.25°:
Products covering: 67°S to 67°N,
180°W to 180°E(2) Resolution=5°:
Products covering: 70°S to 70°N,
180°W to 180°E
Products covering: 67°S to 67°N,
180°W to 180°E

Products covering: 90°S to 90°N,
180°W to 180°E(1) Resolution=0.25°:
Products covering: 67°S to 67°N,
180°W to 180°E(2) Resolution=5°:
Products covering: 70°S to 70°N,
180°W to 180°E
Products covering: 67°S to 67°N,
180°W to 180°E

3.1.2. Definition of GPM Processing Levels
The definitions of the processing levels are shown in Table 3.1-2.

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Table 3.1-2 Definitions of Processing Levels of GPM Product
Processing level
Level 0Level 1A

Level 1B, Level 1C
Level 2

Level 3

Descriptions
The processing input APID Sorted Data (data originated in satellite, packetsynchronized in accordance with CCSDS standard and divided by APIDs). Fromthe primary and secondary headers of the packets, they check the time range, thecontinuousness (data missing) and so on. Level 0 data, which they output, are notprovided to users.
The processing input Level 0 data and output Level 1A data. Level 1A data store
sensor output engineering values, satellite attitude/position, sensor status,transform coefficients and so on in the time range, or scene, of respective files.
L1A data are archived as master data, but not provided to users.
The processing input Level 1A data, conduct geometric corrections, and convert
into received powers, brightness temperatures and so on.
The processing input Level 1 products and derive physical quantities regarding
precipitation, e.g. earth surface scattering cross-sections, precipitation types,
bright band height, attenuation-compensated radar reflectivity factor,
precipitation intensity, latent heating and so on.
The processing input Level 1 or 2 products and conduct spatial and/or temporal
statistical processing.
The output products cover whole globe. The time coverage of the products is one
month, one day or one hour (this goes for global precipitation mapping, latentheating, convective stratiform heating).

3.1.3. Processing Diagram
Figure 3.1-4a, Figure 3.1-4b, Figure 3.1-5a and Figure 3.1-5b show the processing flow of GPM
products.

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GPM Data Utilization Handbook
GMI
GMI L1A

L1

GMI Instrument
Counts

GMI L1B
GMI Brightness
Temperatures(Tb)

GMI

DPR

KuPR
GMI Base

KuPR L1A

KaPR L1A

GMI Antenna
Temperatures

Ku Instrument
CountsKa Instrument
Counts

GMI L1C
GMI Calibrated Tb

KuPR L1B

KaPR L1B

Ku Calibrated
Power

Ka Calibrated
Power

KuPR L2

GMI
PrecipitationGANAL
JMA Global
Analysis data

Ku
Precipitation

GMI L2L2KaPR

DPR/GMI Comb L2

DPR L2

Combined
Precipitation

DPR
Precipitation

GMI L3

DPR/GMI Comb L3

DPR L3

GMI
Precipitation

Combined
Precipitation

DPR
Precipitation

L3

GSMaP
GSMaP L3
Constellation
Radiometers

Global Satellite
Mapping ofPrecipitation

Notes;IR
Gauge

KaPR L2
Ka
Precipitation

DPR Algorithm
GMI Algorithm
Combined Algorithm
Satellite / Auxiliary Data

Figure 3.1-4a Processing Diagram of GPM Products (Precipitation Products)

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DPR

COMB
KuPR L2

KaPR L2

Ku
Precipitation

Ka
Precipitation

DPR/GMI Comb L2

DPR L2

Combined
Precipitation

DPR
Precipitation

L2

DPR/GMI Comb
2H CSH(*1)

DPR 2H SLH

Convective
Stratiform
Heating

L3

Spectral Latent
Heating

DPR/GMI Comb
3G CSHDPR/GMI Comb
3H CSH

Gridded Orbital
Convective
Stratiform Heatingfrom Combined

Monthly
Convective
Stratiform Heatingfrom Combined

DPR 3G SLH

DPR 3H SLH

Gridded Orbital
Spectral Latent
HeatingMonthly
Spectral Latent
Heating

Notes;SLH Algorithm
CSH Algorithm(*1)
2H CSH product isn‘t available from JAXA.

Figure 3.1-4b Processing Diagram of GPM Products(Latent Heating and Convective Stratiform Heating Products)

VIRS

VIRS

L1

TMI

TMI

VIRS L1A

TMI L1A

TMI Base

PR L1A

VIRS Instrument
CountsTMI Instrument
CountsTMI Antenna
Temperatures

PR Instrument
CountsVIRS L1B

TMI L1B

TMI L1C

PR L1B

VIRS
Radiance

TMI Brightness
Temperatures(Tb)

TMI Calibrated Tb

PR Calibrated
Power

TMI L2PR L2TMI
Precipitation

PR
Precipitation

L2

PR/TMI Comb L2

JRA-55JMA Global
Analysis data

Combined
Precipitation

L3

PR

PR

Notes;VIRS Algorithm
TMI Algorithm
PR Algorithm
Combined Algorithm
Satellite / Auxiliary Data

TMI L3

PR/TMI Comb L3

PR L3

TMI
Precipitation

Combined
Precipitation

PR
Precipitation

Figure 3.1-5a Processing Diagram of TRMM Products (Precipitation Products)

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GPM Data Utilization Handbook

COMB

PR

PR/TMI Comb L2

PR L2

Combined
Precipitation

PR
Precipitation

PR/TMI Comb
2H CSHT(*1)

PR 2H SLHT

Convective
Stratiform Heating

Spectral Latent
Heating

L2

L3

PR/TMI Comb
3G CSHT

PR/TMI Comb
3H CSHT

PR 3G SLHT

PR 3H SLHT

Gridded Orbital
Convective
Stratiform Heatingfrom Combined

Monthly
Convective
Stratiform Heatingfrom Combined

Gridded Orbital
Spectral Latent
HeatingMonthly Spectral
Latent Heating

Notes;SLHT Algorithm
CSHT Algorithm(*1)
2H CSHT product isn‘t available from JAXA.

Figure 3.1-5b Processing Diagram of TRMM Products (Precipitation Products)

3.1.4. Products
Table 3.1-3, Table 3.1-4 and Table 3.1-5 respectively show JAXA GPM standard , GPM near-realtime and TRMM standard products.
Standard products are provided with accuracy assurance by JAXA or NASA. Near-real-time
products are intended to be used by meteorological organizations etc. for weather forecast etc. Between
near-real-time products and standard products, there are some differences on the input auxiliary dataor the file coverage in order to shorten latency for near-real-time products.

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Table 3.1-3 List of Standard ProductsGroup

Product

File size (*1)

DPR product KuPR L1B Received Power

Approx. 122.4 MB

KaPR L1B Received Power

Approx. 107.3 MB

Scene unit (*2)

Sampling resolution/
Grid size

Provision frequency

One orbit

Approx. 5 km (*3)(horizontal)
125 m (vertical)

Approx. 16 files/ day

One orbit

Approx. 5 km (*3)(horizontal)
125/250 m (vertical)

Approx. 16 files/ dayApprox. 16 files/ day

KuPR L2 Precipitation

Approx. 209.6 MB

One orbit

Approx. 5 km (*3)(horizontal)
125 m (vertical)

KaPR L2 Precipitation

Approx. 187.4 MB

One orbit

Approx. 5 km (*3)(horizontal)
125/250 m (vertical)

Approx. 16 files/ day

One orbit

Approx. 5 km (*3)(horizontal)
125 m (vertical)

Approx. 16 files/ dayApprox. 16 files/ day

DPR L2 Precipitation

Approx. 397.4 MB

DPR L2 Spectral Latent Heating

Approx. 5 MB

One orbit

Approx. 5 km (*3)(horizontal)
250 m (vertical)

DPR L3TEXT)

Approx. 1.5 MB

Global0.1° grid
67°N–67°S

one file/ dayApprox. 3.2 MB

Global

0.25° grid 67°N–67°S,
5° grid 70°N–70°S

one file/ day

Precipitation(DailyDPR L3 Precipitation (Daily HDF)

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Group

Product

File size (*1)

Scene unit (*2)

Sampling resolution/
Grid size

Provision frequency

Approx. 70 KB

Global

0.25° grid
67°N–67°S

one file/ dayApprox. 70 KB

Global

0.25° grid
67°N–67°S

one file/ day

DPR L3 Precipitation (Monthly
Approx. 968.8 MB
HDF)

Global

0.25° grid 67°N–67°S,
5° grid 70°N–70°S

one file / month

DPR L3 Precipitation (Monthly
Approx. 2 MB
GeoTIFF)

Global

0.25° grid
67°N–67°S

one file / month

DPR L3 Gridded Orbital Spectral
Approx. 770 MB
Latent Heating

One orbit

0.5° grid
67°N–67°S

Approx. 16 files/ day

DPR L3 Monthly Spectral Latent
Approx. 100 MB
HeatingGlobal

0.5° grid
67°N–67°S

one file / month

Approx. 58.3 MB

One orbit

Approx.
6–26km (*3) (horizontal)

Approx. 16 files/ day

GMI
L1C
Inter-Calibrated
Approx. 27.7 MB
Brightness Temperature

One orbit

Approx.
6–26km (*3) (horizontal)

Approx. 16 files/ day

GMI L2 Precipitation

Approx. 16.8 MB

One orbit

Approx.
6–26 km (*3) (horizontal)

Approx. 16 files/ day

GMI L3 Precipitation

Approx. 16.4 MB

Global

0.25° grid
90°N-90°S

one file/ month

DPR L3 Precipitation
Ascending GeoTIFF)(DailyDPR L3 Precipitation
Descending GeoTIFF)(Daily

GMI product GMI L1B Brightness Temperature

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Group
DPR/GMI
combined
product

GSMaP
product

Product

File size (*1)

COMB L2 Precipitation

Approx. 121.3 MB

Scene unit (*2)

Sampling resolution/
Grid size

Provision frequency

GlobalApprox.
5 km (*3) (horizontal)

Approx. 16 files/ day

one file/ month

COMB L3 Precipitation

Approx. 596.2 MB

Global

0.25° grid
67°N–67°S
5° grid
70°N–70°S

COMB L3 Gridded Orbital
Spectral Latent Heating *3

Approx. 5MB

Global

0.25° grid
67°N–67°S

Approx. 16 files/ day

COMB L3 Monthly Spectral
Latent Heating*3

Approx. 40MB

Global

0.25° grid
67°N–67°S

one file/ month

GSMaP
HDF)

Precipitation(Hourly

Approx. 4.7 MB

Global0.1° grid
90°N–90°S

24 files/ day

GSMaP
TEXT)

Precipitation(Hourly

Approx. 12.5 MB

Global0.1° grid
90°N–90°S

24 files/ day

GSMaP Precipitation
GeoTIFF)(Hourly

Approx. 1.5MB

Global0.1° grid
90°N-90°S

24 files/ day

GSMaP Precipitation
NetCDF)(Hourly

Approx. 4.5MB

Global0.1° grid
90°N–90°S

24 files/ day

GSMaP
HDF)

Precipitation(Monthly

Approx. 41.6 MB

Global0.1° grid
90°N–90°S

one file/ month

GSMaP Precipitation
GeoTIFF)(Monthly

Approx. 15 MB

Global0.1° grid
90°N–90°S

one file/ month

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Group

Product

Scene unit (*2)

Sampling resolution/
Grid size

Provision frequency

Global0.1° grid
90°N–90°S

one file/ month

DMSP F16 SSMIS L1C InterApprox. 22.9 MB
Calibrated Brightness Temperature

One orbit

Approx.
13–69km (horizontal)

14 files/ dayDMSP F17 SSMIS L1C InterApprox. 22.7 MB
Calibrated Brightness Temperature

One orbit

DMSP F18 SSMIS L1C InterApprox. 21.7 MB
Calibrated Brightness Temperature

One orbit

Approx.
13–69km (horizontal)

14 files/ dayDMSP F19 SSMIS L1C InterApprox. 23.1 MB
Calibrated Brightness Temperature

One orbit

Approx.
13–69km (horizontal)

14 files/day

METOP-A MHS L1C InterApprox. 3.9 MB
Calibrated Brightness Temperature

One orbit

Approx.
30–50km (horizontal)

14files/ day

METOP-B MHS L1C InterApprox. 3.9 MB
Calibrated Brightness Temperature

One orbit

Approx.
30–50km (horizontal)

14 files/ day

NOAA-18 MHS L1C InterApprox. 3.9 MB
Calibrated Brightness Temperature

One orbit

Approx.
30–50km (horizontal)

14 files/ day

NOAA-19 MHS L1C InterApprox. 3.9 MB
Calibrated Brightness Temperature

One orbit

Approx.
30–50km (horizontal)

14 files/ day

NPP ATMS L1C Inter-Calibrated
Approx. 11.9 MB
Brightness Temperature

One orbit

Approx.
1.1–5.2° (horizontal)

14 files/ day

Megha Tropiques SAPHIR L1C
Inter-Calibrated
Brightness Approx. 9.7 MB
Temperature

One orbit

Approx.
10 km (horizontal)

14 files/ day

GSMaP Precipitation
NetCDF)

Constellation satellite
L1C productFile size (*1)(Monthly

Approx. 41.6MB

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Approx.
13–69km (horizontal)

14 files/ dayGPM Data Utilization Handbook

Group

Product

File size (*1)

Scene unit (*2)

Sampling resolution/
Grid size

Provision frequency

GCOM-W AMSR2 L1C InterApprox. 83.3 MB
Calibrated Brightness Temperature

One orbit

Approx.
5–50km (horizontal)

15 files/ day

TRMM TMI L1C Inter-Calibrated
Approx. 13.7 MB
Brightness Temperature

One orbit

Approx.
2.5 km (horizontal)

16 files/ dayENV

KuPR Environment Auxiliary

Approx. 644 MB

One orbit

Approx.
5 km (*3) (horizontal)

Approx. 16 files/ dayproduct

KaPR Environment Auxiliary

Approx. 484 MB

One orbit

Approx.
5 km (*3) (horizontal)

Approx. 16 files/day

DPR Environment Auxiliary

Approx. 805 MB

One orbit

Approx.
5 km (*3) (horizontal)

Approx. 16 files/day(*1) The product of this HDF form indicates actual file size (internal compression).
(*2) 3.1.1 shows the definitions of scene unit for products created in GPM mission operation system.
Data that will no longer be provided as of October 2020 are grayed out.
(*3) These values are before the rise of the satellite altitude. See the table 2.2-1 and 2.2-3 since the rise of the altitude in November 2023.

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Table 3.1-4 List of Near-real-time ProductsGroup

Product

DPR product

KuPR L1B Received Power_nrt

Approx.
39.6 MB

KaPR L1B Received Power_nrt

Approx.
35.0 MB

KuPR L2 Precipitation_nrt

Approx.
67.7 MB

GMI productFile size

Scene unit (*1)

Sampling resolution/
Grid size

Provision
frequency

Provision latency fromthe observation (*2)

30 minutes

Approx. 5 km (*3)(horizontal)
125 m (vertical)

48 files/ dayApprox. 60 minutes

30 minutes

Approx. 5 km (*3)(horizontal)
125/250 m (vertical)

48 files/ dayApprox. 60 minutes

30 minutes

Approx. 5 km (*3)(horizontal)
125 m (vertical)

48 files/ dayApprox. 65 minutes

KaPR L2 Precipitation_nrt

Approx.
60.7 MB30 minutes

Approx. 5 km (*3)(horizontal)
125/250 m (vertical)

48 files/ dayApprox. 65 minutes

DPR L2 Precipitation_nrt

Approx.
128.3 MB30 minutes

Approx. 5 km (*3)(horizontal)
125 m (vertical)

48 files/ dayApprox. 70 minutes

Brightness Approx.
3.6 MB

5 minutes

Approx.
6–26 km (*3) (horizontal)

288 files/ dayApprox. 20 minutes

GMI
L1C
Inter-Calibrated Approx.
Brightness Temperature_nrt
1.6 MB

5 minutes

Approx.
6–26km (*3) (horizontal)

288 files/ dayApprox. 20 minutes

5 minutes

Approx.
6–26km (*3) (horizontal)

288 files/ dayApprox. 25 minutes

GMI
L1B
Temperature_nrt

GMI L2 Precipitation_nrt

Approx.
1.0 MB

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Group

Product

DPR/GMI
combined
product

COMB L2 Precipitation_nrt

GSMaP
product

Constellation
satellite
L1C productFile size

Scene unit (*1)

Sampling resolution/
Grid size

Provision
frequency

Provision latency fromthe observation (*2)

30 minutes

Approx. 5 km (*3)(horizontal)

48 files/ dayApprox. 85 minutes

GSMaP Precipitation (Hourly Approx.
HDF)_nrt
2.5 MB

global0.1° grid
90°N–90°S

24 files/ dayApprox. 255 minutes

GSMaP Precipitation (Hourly Approx.
TEXT)_nrt
3.4 MB

global0.1° grid
90°N–90°S

24 files/ dayApprox. 255 minutes

DMSP F16 SSMIS L1C InterApprox.
Calibrated
Brightness
24.1 MB
Temperature_nrt

One orbit

Approx.
13–69 km (horizontal)

14 files/ dayApprox. 130 minutes

DMSP F17 SSMIS L1C InterApprox.
Calibrated
Brightness
23.9 MB
Temperature_nrt

One orbit

Approx.
13–69 km (horizontal)

14 files/ dayApprox. 150 minutes

DMSP F18 SSMIS L1C InterApprox.
Calibrated
Brightness
22.5 MB
Temperature_nrt

One orbit

Approx.
13–69 km (horizontal)

14 files/ dayApprox. 130 minutes

METOP-A MHS L1C InterApprox.
Calibrated
Brightness
3.9 MB
Temperature_nrt

One orbit

Approx.
30–50 km (horizontal)

14 files/ dayApprox. 155 minutes

METOP-B MHS L1C InterApprox.
Calibrated
Brightness
2.3 MB
Temperature_nrt

One orbit

Approx.
30–50 km (horizontal)

14 files/ dayApprox. 105 minutes

Approx.
38.4 MB

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Group

Product

File size

Scene unit (*1)

Sampling resolution/
Grid size

Provision
frequency

Provision latency fromthe observation (*2)

NOAA-18 MHS L1C InterApprox.
Calibrated
Brightness
4.1 MB
Temperature_nrt

One orbit

Approx.
30–50 km (horizontal)

14 files/ dayApprox. 300 minutes

NOAA-19 MHS L1C InterApprox.
Calibrated
Brightness
4.2 MB
Temperature_nrt

One orbit

Approx.
30–50 km (horizontal)

14 files/ dayApprox. 160 minutes(*1) 3.1.1 shows the definitions of scene unit for products created in GPM mission operation system.
(*2) The values are based on the actual operation from June 5th to 9th, 2014.
Data that will no longer be provided as of October 2020 are grayed out.
(*3) These values are before the rise of the satellite altitude. See the table 2.2-1 and 2.2-3 since the rise of the altitude in November 2023.

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Table 3.1-5 List of Standard ProductsGroup

Product

File size(*1)

Scene unit (*2)

PR productSampling resolution/
Grid size

Provision frequency

Approx. 16 files/ day

PR L1B Received Power

Approx. 122.4 MB

One orbit

Approx.
4.3–5 km (horizontal)
250 m (vertical)

PR L2 Precipitation

Approx. 209.6 MB

One orbit

Approx.
4.3–5 km (horizontal)
250 m (vertical)

Approx. 16 files/ dayApprox. 16 files/ day

PR L2 Spectral Latent Heating

Approx. 5 MB

One orbit

Approx.
4.3–5 km (horizontal)
250 m (vertical)

PR L3 Precipitation (Daily TEXT)Approx. 1.5 MB

Global0.1° grid
67°N–67°S

one file/ day

PR L3 Precipitation (Daily HDF)

Approx. 3.2 MB

Global

0.25° grid
67°N–67°S

one file/ day

PR L3 Precipitation (Monthly
Approx. 968.8 MB
HDF)

Global

0.25° grid
67°N–67°S
5° grid
70°N–70°S

one file / month

PR L3 Gridded Orbital Spectral
Approx. 770 MB
Latent Heating

One orbit

0.5° grid
67°N–67°S

Approx. 16 files/ day

PR L3 Monthly Spectral Latent
Approx. 100 MB
HeatingGlobal

0.5° grid
67°N–67°S

one file / month

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GPM Data Utilization Handbook

Group
TMI product

PR/TMI
combined
product

Sampling resolution/
Grid size

Provision frequency

One orbit

Approx.
6–50 km (horizontal)

Approx. 16 files/ day

TMI
L1C
Inter-Calibrated
Approx. 27.7 MB
Brightness Temperature

One orbit

Approx.
6–50 km (horizontal)

Approx. 16 files/ day

TMI L2 Precipitation

Approx. 16.8 MB

One orbit

Approx.
6–50 km (horizontal)

Approx. 16 files/ day

TMI L3 Precipitation

Approx. 16.4 MB

Global

0.25° grid
90°N–90°S

one file/ month

COMB L2 Precipitation

Approx. 121.3 MB

One orbit

Approx.
5 km (horizontal)

Approx. 16 files/ day

Global

0.25° grid
67°N–67°S
5° grid
70°N–70°S

one file/ month

COMB L3 Gridded Orbital Spectral
Approx. 5 MB
Latent Heating *3

One orbit

0.25° grid
67°N–67°S

Approx. 16 files/ day

COMB L3 Monthly Spectral Latent
Approx. 40 MB
Heating*3

Global

0.25° grid
67°N–67°S

one file/ month

VIRS L1B Radiance

One orbit

Approx.
2 km (horizontal)

Approx. 16 files/ day

Product

File size(*1)

TMI L1B Brightness Temperature

Approx. 58.3 MB

COMB L3 Precipitation

VIRS
product

Approx. 596.2 MBApprox. 230 MB

Scene unit (*2)

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GPM Data Utilization Handbook

Group
ENV
product

Product

PR Environment Auxiliary

File size(*1)

Approx. 644 MB

Scene unit (*2)

One orbit(*1) The product of this HDF form indicates actual file size (internal compression).
(*2) 3.1.1 shows the definitions of scene unit for products created in GPM mission operation system.
(*3) Processed by PPS

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Sampling resolution/
Grid size

Provision frequency

Approx.
4.3–5 km (horizontal)
250 m (vertical)

Approx. 16 files/ dayGPM Data Utilization Handbook

3.1.5. File Naming Conventions
Granule IDs are employed as file names of products. Granule ID identifies the earth observation
satellite data. Granule IDs of level 1 to 3 products consist of “scene ID” and “product ID”. “Scene ID”
part includes mission ID, sensor ID, scene start/end time, and so on. “Product ID” part includes
algorithm ID and so on. File naming conventions are described below.

(1) L1 and L2 Standard Products
All level 1 and level 2 standard products fall under this category. Table 3.1-6 shows the naming
convention for L1 and L2 standard products.
Table 3.1-6 Naming Convention for L1 and L2 standard products

Field name

Field
Width

Mission ID(1) (Mission name +Satellite ID)

6(2) Sensor ID

3(3) Scene Start(4) Scene End(5) Orbit Number
Process Level(6)(Level+Type)1046(7) Algorithm Key

3(8) Product Version

3

3

Description
GPM (GPM mission, fixed),
xxx (COR: GPM core satellite, etc. See Table 3.1-15)
sss (KUR: KuPR, KAR: KaPR, CMB: DPR/GMI combined, etc.
See Table 3.1-15)
YYMMDDhhmm (UTC)hhmm (UTC)nnnnnn (000001–999999)
LL (1B: Level 1B, 1C: Level 1C, L2: Level 2)
S (Standard, fixed)
Identify Algorithm name & Developer
See Table 3.1-16
VV (01–99, Major; count up at re-processing)v (A–Z, Minor)

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GPM Data Utilization Handbook(2) L1 and L2 Near-real-time Products
All level 1 and level 2 near-real-time products fall under this category. Table 3.1-7 shows the naming
convention for L1 and L2 near-real-time products.

Table 3.1-7 Naming Convention for L1 and L2 Near-real-time Products

JAXA field nameMission ID(1) (Mission name +Satellite ID)

Field
Width
6

(2) Sensor ID

3(3) Scene Start (UTC)(4) Scene End (UTC)104(5) Process Level

3(6) Algorithm Key

3(7) Product Version

3

Description
GPM (GPM mission, fixed),
xxx (COR: GPM core satellite, etc. See Table 3.1-15)
sss (KUR: KuPR, KAR: KaPR, CMB: DPR/GMI combined, etc.
See Table 3.1-15)
YYMMDDhhmm (UTC)hhmm (UTC)
LL (1B: Level 1B, 1C: Level 1C, L2: Level 2)
R (Near real time, fixed)
Identify Algorithm name & Developer
See Table 3.1-16
VV (01–99, Major; count up at re-processing)v (A–Z, Minor)

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GPM Data Utilization Handbook(3) L3 (Hourly) Standard/Near-real-time Products
Global Satellite Mapping of Precipitation level 3 (NRT and STD) fall under this category. Table
3.1-8 shows the naming convention for L3 (Hourly) standard/near-real-time products.
Table 3.1-8 Naming Convention for L3 (Hourly) Standard/Near-real-time Products

JAXA field nameMission ID(1) (Mission name +Satellite ID)(2) Sensor ID

Field
Width
6

Description
GPM (GPM mission, fixed),
MRG (GPM merge, fixed)

3

MAP (Global Satellite Mapping of Precipitation, fixed)(3) Scene Start (UTC)10YYMMDDhhmm (UTC)(4) Process Unit

1

H (Hourly, fixed)(5) Process Level

3(6) Algorithm Key

3(7) Product Version

3

L3 (Level 3, fixed)t (S: Standard, N: Near real time)
Identify Algorithm name & Developer
See Table 3.1-16
VV (01–99, Major; count up at re-processing)v (A–Z, Minor)

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GPM Data Utilization Handbook(4) L3 (Daily) Standard Products
PR and DPR level 3 falls under this category. Table 3.1-9 shows the naming convention for L3(Daily) standard products.
Table 3.1-9 Naming Convention for L3 (Daily) Standard Products

JAXA field name

Field
Width

Description

Mission ID(1) (Mission name +Satellite ID)(2) Sensor ID

3

DPR (DPR: DPR, KUR: PR)(3) Scene Start (UTC)6YYMMDD (UTC)(4) Process Unit

1

D (Daily)(5) Process Level

3(6) Algorithm Key

3(7) Product Version

3

6

GPM (GPM mission, fixed),
COR (GPM core satellite, fixed)

L3 (L3: Level 3, fixed)
S (Standard, fixed)
Identify Algorithm name & Developer
See Table 3.1-16
VV (01–99, Major; count up at re-processing)v (A–Z, Minor)

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GPM Data Utilization Handbook(5) L3 (Monthly) Standard Products
DPR level 3, DPR/GMI combined level 3, Global Satellite Mapping of Precipitation level 3, GMI
level 3, PR level 3, PR/TMI combined level 3 and TMI level 3 fall under this category. Table 3.1-10
shows the naming convention for L3 (Monthly) standard products.
Table 3.1-10 Naming Convention for L3 (Monthly) Standard Products

JAXA field name

Field
Width

Description
GPM (GPM mission, fixed),
xxx (COR: GPM core satellite, etc. See Table 3.1-15)

Mission ID(1) (Mission name +Satellite ID)

6(2) Sensor ID

3(3) Scene Start (UTC)4

sss (KUR: KuPR, KAR: KaPR, CMB: DPR/GMI combined, etc.
See Table 3.1-15)
YYMM (UTC)(4) Process Unit

1

M (Monthly)(5) Process Level

3(6) Algorithm Key

3(7) Product Version

3

L3 (Level 3, fixed)
S (Standard, fixed)
Identify Algorithm name & Developer
See Table 3.1-16
VV (01–99, Major; count up at re-processing)v (A–Z, Minor)

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GPM Data Utilization Handbook(6) GSMaP L3 Standard products (GeoTIFF)
GSMaP level 3 (GeoTIFF) falls under this category. Table 3.1-11 shows the naming convention for
GSMaP L3 (Hourly, GeoTIFF) standard products and GSMaP L3 (Monthly, GeoTIFF) standard
products.
Table 3.1-11 Naming Convention for L3 GSMaP (GeoTIFF) Standard Products

JAXA field name

Field
Width

Description

Mission ID(1) (Mission name +Satellite ID)(2) Sensor ID

6

GPM (GPM mission, fixed),
MRG (GPM merge, fixed)

3

MAP (Global Precipitation Map, fixed)(3) Scene Start (UTC)4,10(4) Process Unit

1(5) Process Level

3(6) Algorithm Key

3(7) Product Version

3(8) Variable

3

YYMM (UTC)YYMMDDhhmm (UTC)M (Monthly), H (Hourly)
L3 (Level 3, fixed)
S (Standard, fixed)
MCH (Hourly)/MCM (Monthly)
VV (01–99, Major; count up at re-processing)v (A–Z, Minor)
PRC (Precipitation Rate, fixed)

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GPM Data Utilization Handbook(7) DPR L3 Standard Products (GeoTIFF)
DPR level 3 (Daily, GeoTIFF) and DPR level 3 (Monthly, GeoTIFF) falls under this category. Table
3.1-12 shows the naming convention for DPR L3 (Daily, GeoTIFF) standard products.
Table 3.1-12 Naming Convention for L3 DPR (GeoTIFF) Standard Products

JAXA field name

Field
Width

Description

6

GPM (GPM mission, fixed),
COR (GPM core satellite, fixed)(2)

Mission ID(Mission name +Satellite ID)
Sensor ID

3

DPR (fixed)(3)

Scene Start (UTC)4, 6

YYMMDD (Daily, UTC), YYMM (Monthly, UTC)

(4)

Process Unit

1

D (Daily)/M (Monthly)(5)

Process Level

3(6)

Algorithm Key

3(7)

Product Version

3(8)

Variable3v (A–Z, Minor)
PRC (Hourly Precipitation Rate, fixed)(9)Orbit Type

1

O (A: Ascending, D: Descending)(10) Sensor Type

3

SSS （KUF: KuFS, KAF: KaFS, DPF: DPRFS）(11) Rain Type3

RTY （STR：Stratiform, CON: Convective, ALL: All）

(1)

L3 (Level 3, fixed)
S (Standard, fixed)
D3Q (Daily)/D3M (Monthly)
VV (01–99, Major; count up at re-processing)

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GPM Data Utilization Handbook(8) GPM Latent Heating L3 Standard products(Orbital)
3GSLH, 3GCSH, 3GSLHT, 3GCSHT falls under this category. Table 3.1-13 shows the naming
convention for LH L3 Standard product.
Table 3.1-13 Naming Convention for LH Standard Products

JAXA field name

Field
Width

GPM (GPM mission, fixed),

Mission ID(1)(Mission name +Satellite ID)

Description

6

COR (GPM core satellite) / TRM (TRMM satellite)
DPR (for SLH, fixed)(2)

Sensor ID

3

CMB (for CSH or CSHT)
KUR (for SLHT, fixed)(3)

Scene Start (UTC)8

YYMMhhmm (UTC)(4)

Scene End (UTC)4hhmm (UTC)(5)

Orbit Number

6

nnnnnn: 000000–999999(6)

Process Level

3(7)

Algorithm Key

3(8)

Product Version

3

L3 (Level 3, fixed)
S (Standard, fixed)
SLG (SLH L3 gridded orbit), LHG (SLHT L3 gridded orbit),
CSG (CSH L3 gridded orbit), CSH (CSHT L3 gridded orbit)
VV (01–99, Major ; count up at re-processing)v (A–Z, Minor)

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GPM Data Utilization Handbook(9) GPM Environment Auxiliary (ENV) Products
KuPR, KaPR, DPR Environment Auxiliary (ENV) products falls under this category. Table 3.1-14
shows the naming convention for ENV L2 standard products.
Table 3.1-14 Naming Convention for GPM Environment Auxiliary (ENV) Products

JAXA field name

Field
Width

Description

6

GPM (GPM mission, fixed),
COR (GPM core satellite)/TRM (TRMM satellite)3

sss (KUR: KuPR, KAR:KaPR, DPR:DPR)(2)

Mission ID(Mission name +Satellite ID)
Sensor ID(3)

Scene Start (UTC)10YYMMDDhhmm (UTC)(4)

Scene End (UTC)4hhmm (UTC)(5)

Orbit Number

6

nnnnnn (000001–999999)(6)

Process Level

3(7)

Algorithm Key

3(8)

Product Version

3(1)

LL ( L2: Level 2)
S (Standard)
DU2 (KuPR L2), DA2 (KaPR L2), DD2 (DPR L2), PU2 (PR L2)
VV (01–99, Major; count up at re-processing)v (A–Z, Minor)

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GPM Data Utilization Handbook

As complementary information on the naming conventions, see Table 3.1-15 for satellite IDs andsensor IDs, and Table 3.1-16 for algorithm keys.
Table 3.1-15 Satellite IDs and Sensor IDs
Satellite

GPM Core

Megha Tropiques
GCOM-WDMSP F16
DMSP F17DMSP F18
DMSP F19
NOAA-18
NOAA-19NPPNOAA-20
NOAA-21
METOP-A
METOP-B
METOP-CTRMM

Sensor
KuPR
KaPR
DPR
GMI
Combined Products
Map Products
MADRASSAPHIR
AMSR2
SSMIS
SSMIS
SSMIS
SSMIS
MHS
MHS
ATMS
ATMS
ATMS
MHS
MHS
MHS
PR
TMI
VIRS
Combined Products

Satellite ID(3 char)Sensor ID(3 char)

COR
COR
COR
COR
COR
MRG
MGT
MGT
GW1
F16
F17
F18
F19
N18
N19
NPP
N20
N21
MTA
MTB
MTC
TRM
TRM
TRM
TRM

KUR
KAR
DPR
GMI
CMB
MAP
MDR
SPH
AM2
MIS
MIS
MIS
MIS
MHS
MHS
ATS
ATS
ATS
MHS
MHS
MHS
KUR
TMI
VIR
CMB

Table 3.1-16 Algorithm Keys
Processing Algorithm
KuPR Level 1B
KaPR Level 1B
KuPR Level 2
KaPR Level 2
DPR Level 2
DPR Level 3 (Daily, Text)
DPR Level 3 (Daily, HDF5)

Algorithm Key(3 char)
DUB
DAB
DU2
DA2
DD2
D3D
D3Q

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GPM Data Utilization Handbook

Processing Algorithm
DPR Level 3 (Daily, Ascending, GeoTIFF)
DPR Level 3 (Daily, Descending, GeoTIFF)
DPR Level 3 (Monthly, HDF)
DPR Level 3 (Monthly, GeoTIFF)
GMI Level 1B (PPS processing)
GMI Level 1C (PPS processing)
GMI Level 2 (PPS processing)
GMI Level 3 (PPS processing)
DPR/GMI Combined Level 2 (PPS processing)
DPR/GMI Combined Level 3 (PPS processing)
MWI/MWS Level 1C (PPS processing)
GSMaP (Hourly, Standard, HDF5)
GSMaP (Hourly, Standard, Text)
GSMaP (Hourly, Standard, GeoTIFF)
GSMaP (Hourly, Standard, NetCDF)
GSMaP (Hourly, Near-Real-Time, HDF5)
GSMaP (Hourly, Near-Real-Time, Text)
GSMaP (Monthly HDF)
GSMaP (Monthly GeoTIFF)
GSMaP (Monthly NetCDF)
SLH-DPR Level 2 (Pixel Swath)
SLH-DPR Level 3 (Gridded Orbit)
SLH-DPR Level 3 (Monthly)
DPR/GMI Combined LH Level 3 (Gridded Orbit)
DPR/GMI Combined LH Level 3 (Monthly)
KuPR Environment Auxiliary data
KaPR Environment Auxiliary data
DPR Environment Auxiliary data
PR Level 1B
PR Level 2
SLH-PR Level 2 (Pixel Swath)
PR Level 3 (Daily, Text)
PR Level 3 (Daily, HDF5)
PR Level 3 (Monthly, HDF)
SLH-PR Level 3 (Gridded Orbit)
SLH-PR Level 3 (Monthly)
TMI Level 1B (PPS processing)
TMI Level 2 (PPS processing)
TMI Level 3 (PPS processing)
PR/TMI Combined Level 2 (PPS processing)

3-31

Algorithm Key(3 char)
D3Q
D3Q
D3M
D3M
G1B
G1C
GL2
GL3
CL2
CL3
Sensor ID
Refer to Table 3.1-16
MCH
MCT
MCH
MCN
MFW
MFT
MCM
MCM
MCN
SLP
SLG
SLM
CSG
CSM
DU2
DA2
DD2
PU1
PU2
LHP
P3Q
P3D
P3M
LHG
LHM
TMI
TL2
TL3
TC2

GPM Data Utilization Handbook

Processing Algorithm

Algorithm Key(3 char)

PR/TMI Combined Level 3 (PPS processing)
TC3
VIRS Level 1B (PPS processing)
V1B
PR Environment Auxiliary data
PU2
Note: SLH: Spectral Latent Heating, LH: Latent Heating
The following products are originally named by NASA/PPS, then renamed to meet the granule IDconventions and provided via G-Portal. The naming conventions described in this subsection are theones after renamed.
-

GPM core satellite, sensor ID: GMI/CMB, all level-

GPM constellation satellites, level 1C

Therefore, please note that products above are provided with different names between JAXA andNASA/PPS.

3.1.6. Products Format(1) GPM products Format
GPM Product are provided on HDF (Hierarchical Data Format) file format. This file format is internallycompressed format and useful to address multi-dimensional arrays. GPM products adopt HDF5 ver1.8.9.
TKIO can manage data in HDF5 files, specified by user programs.

(2) What is HDF?
HDF is a set of file formats developed by the NCSA (The National Center for Supercomputing Application/ University of Illinois) and platform independent formats. There are 2 types of HDF, HDF4 and HDF5.
HDF5 modified some problems of HDF4 (limitation of data size, multiple data types and others). HDF fileconsists of 2 parts, the one part is “Attribute” which contains attribute information and the other is “Dataset”
which contains product data itself. Attribute of GPM products contains metadata, and Dataset contains
product data such as observation data, latitude/longitude data and others.

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GPM Data Utilization Handbook

GPM Products
Attribute
Metadata
DatasetObservation
data
Observation
data
Observation

Received
power
Received
power

data

Figure 3.1-6 Structure of HDF file(3) How to get HDF5 library
HDF5 library files are available at the HDF group website. The latest version of HDF5 library is available
on the website shown below;
https://portal.hdfgroup.org/downloads/index.html
The Table 3.1-17 shows the library files as of June 2014. You can download the HDF5 library suitable foryour platform. Although GPM Products’ version of HDF5 is different from current library, the library version
is compatible with GPM Products’.

Table 3.1-17 HDF5 library
Platform

Filename

Notes

All Platform

src/hdf5-1.8.13.tar.gz

Source CodeLinux 2.6 i686

hdf5-1.8.13-linux-shared.tar.gz

Binary (shared)

Linux 2.6 x86_64

hdf5-1.8.13-linux-x86_64-shared.tar.gz

Binary (shared)

HDF library uses the sz library. You need to download sz library if you don’t install.
Table 3.1-18 sz library
URL

Notes

https://support.hdfgroup.org/ftp/lib-external/szip/

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GPM Data Utilization Handbook(4) Data Structure Outline of GPM Products using HDF5
Figure 3.1-7 shows the data structure outline of level 1B Ku product (V05C) as an example. The level 1B
Ku product consists of two components. The first component is product metadata (Product Metadata) and thesecond is science data (Data Group). Product metadata has six variables; FileHeader, InputRecord,
NavigationRecord, FileInfo, JAXAInfo and DPRKuInfo. On the other hand, science data has one metadataand several data groups. Each variable is specific array type and byte size.
Data structure of GPM products is described in each product format documentation.

Figure 3.1-7 The Data Structure Outline of Level 1B Ku Product

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GPM Data Utilization Handbook

3.1.7. Conceptual Explanation of Product/Algorithm Versions
Product/Algorithm versions are controlled by JAXA responsible for data distribution, and version up
depending on the results from calibration and validation process during operational phase after the launch.
Product versions is shown in 2.4 File Naming Conventions as the products definition including productversion by 3 numbers of characters; Major (2 digits, such as 01, 02, 03…) + Minor (1 letter, such as a, b,c…), where major shows increment at re-processing after the launch from 01.

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GPM Data Utilization Handbook

3.2. Processing Description
3.2.1. DPR Product(1) Level 1
In DPR level 1B standard processing, a level 1A product is read as input data and a productcontaining a received power profile and geometric information, such as observation positions, isoutputted. During the course of processing, radiometric correction is carried out, missing data isprocessed based on missing data information, scan time is corrected and geometric calculation of thetime, latitude, longitude, and height of each piece of scan data in each range bin is performed.
The processing described above is carried out for KuPR and KaPR radar input values. Figure 3.2-1
shows the processing flow.

Level 1A product input
Missing data processing
Scan time correction
Geometric calculation
Radiometric correction
Level 1B product output
Figure 3.2-1 Level 1B Standard Processing Flow

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GPM Data Utilization Handbook(2) Level 2
The level 2 processing algorithm of the dual frequency precipitation radar additionally uses received
power value profiles observed by KuPR and KaPR to estimate a precipitation intensity profile. It also
estimates precipitation type, precipitation top height, and bright band height.
“Figure 3.2-2 DPR L2 Processing Flow” shows the flow of the algorithm.

Figure 3.2-2 DPR L2 Processing Flow
Level 2 algorithm input data is a level 1 DPR product (P (γ) calibrated radar echo power value
profile), and level 2 algorithm output data is a level 2 product (precipitation intensity profile).
KuPR, KaPR, and dual frequency precipitation radar (DPR) products are created by the standard
algorithm. For a KuPR product, the level 2 algorithm uses only observation data obtained by KuPR toestimate precipitation. For a KaPR product, the level 2 algorithm uses only observation data obtainedby KaPR to estimate precipitation. For a dual frequency precipitation product, the algorithm uses KuPR
and KaPR observation data to estimate precipitation. In areas with the KuPR observation, the level 2
algorithm uses the observation data by KuPR and also information obtained from observation by KuPR
and KaPR.

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GPM Data Utilization Handbook(3) Level 3
Level 3 standard processing algorithm flow is shown in Figure 3.2-3. A/D means
Ascending/Descending. Monthly products are created by 28–30 daily products on data stack. HDF
products, daily/monthly, are processed by the algorithm developed by NASA and text product, daily,
is processed by the algorithm developed by JAXA.

Figure 3.2-3 Flow of the L3 Processing Algorithm

3-38

GPM Data Utilization Handbook(4) Environment Auxiliary (ENV)
Environment Auxiliary (ENV) is Meteorological analysis data used as an input data to the level 2
processing shown. They are the Japanese Global Analysis model data (GANAL) used to provide
atmospheric environmental conditions.
In the current algorithm formulation, only the analysis data such as analysis data, must be integrated
from an external source during combined algorithm processing.
Analysis data are required to produce initial estimations of environmental parameters such as total
precipitable water, TPWanal, cloud liquid water path, CLWPanal, surface skin temperature, Tsfcanal,and 10m altitude wind speed, U10manal. The current algorithm design requires space-time
interpolation of these data from the Japanese Meteorological agency’s (JMA) global analysis(GANAL) during standard algorithm processing. The data are interpolated to the DPR footprint/range
bin locations and overpass times in the Vertical Profile Submodule (VER) of the Level 2 Radar
Algorithm and then output. For near realtime processing, the JMA forecast fields, but if these fields
are not received in time for any reason, the climate value data are substituted for the JMA
analysis/forecast data in the VER processing.

Table 3.2-1 Environment Auxiliary (ENV)
Auxiliary
GPM KuPR

Description
Main parameters: Air temperature, Air pressure, Water vapor,

Environment Cloud liquid water
Auxiliary

Swath width: ≥ Approx. 245 km*(ENV)

Resolution: ≥ Approx. 5 km* (horizontal), 125 m (vertical)

GPM KaPR

Main parameters: Air temperature, Air pressure, Water vapor,

Environment Cloud liquid water
Auxiliary

Swath width: ≥ Approx. 245 km*(ENV)

Resolution: ≥ Approx. 5 km* (horizontal), 125/250 m (vertical)

GPM DPR

Main parameters: Air temperature, Air pressure, Water vapor,

Environment Cloud liquid water
Auxiliary

Swath width: ≥ Approx. 245 km*(ENV)

Resolution: ≥ Approx. 5 km* (horizontal), 125/250 m (vertical)* These values are before the rise of the satellite altitude. See the table 2.2-1 and 2.2-3 since
the rise of the altitude in November 2023.

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GPM Data Utilization Handbook(5) Spectral Latent Heating ProductAt level 2 processing, spectrum latent heating (2HSLH), and vertical distribution of Q1-QR and Q2
is obtained from DPR rain rate product. Granule size is one orbit.
In Gridded Orbital Spectral Latent Heating (3GSLH) products, latent heating of 0.5 degree grid andvertical distribution of Q1-QR and Q2 are obtained from DPR rainfall.
The Monthly Spectral Latent Heating (3HSLH) products are processed by same procedure 3GSLH.
In the composite product, Gridded Orbital Convective Stratiform Heating from the Combined(3GCSH) product, 0.25 degrees grid and the just below the orbit apparent heating profile are obtained
from convective and stratiform rainfall of the ground surface. And Monthly Convective Stratiform
Heating from Combined (3HCSH) obtained apparent heating profile from convective and stratiform
rainfall of the land surface of 0.25 degrees grid.

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GPM Data Utilization Handbook

3.2.2. Global Satellite Mapping of Precipitation
The global satellite mapping of precipitation (GSMaP) algorithm is a map creation algorithm whose
accuracy has been improved by DPR data and information. It generates a map of global satellite
mapping of precipitation, which is a spatial-temporally averaged level 3 product, by combining:
estimated precipitation based on readings of multiple microwave radiometers (imager/sounder)
including a GPM microwave radiometer (GMI); and cloud travel information obtained fromgeostationary infrared (IR) data. “Figure 3.2-4 GSMaP Processing Flow” gives an overview of theprocessing flow.

Figure 3.2-4 GSMaP Processing Flow
The GSMaP algorithm can be roughly divided into the following three algorithms: microwave
imager (MWI) algorithm, microwave sounder (MWS) algorithm, and microwave-Infrared (IR) combined(MVK) algorithm.
A global satellite mapping of precipitation can be subject to standard processing or near real-timeprocessing. In standard processing, hourly observation data is processed and data is averaged monthly. Near
real-time processing provides a higher data frequency than standard processing (every hour).

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3.2.3. PR Product(1) Level 1
In PR Level 1B standard processing, a Level 1A product is read as input data and a productcontaining a received power profile and geometric information, such as observation positions, isoutputted. During the course of processing, radiometric correction is carried out, missing data areprocessed based on missing data information, and geometric calculation of each footprint is performed.
Figure 3.2-5 shows the processing flow.

Figure 3.2-5 Level 1B Processing Flow

(2) Level 2
Level 2 processing of the TRMM/PR is same as that of the GPM/DPR, described in Section 3.2.1(2)except for no-input of the KaPR product. TRMM/PR is a Ku-band radar and corresponds to the
GPM/KuPR. We provide long-term homogeneous products, by applying common processing
algorithms in TRMM and GPM, as well as product format.

(3) Level 3
Level 3 processing of the TRMM/PR is same as that of the GPM/DPR, described in Section 3.2.1(3),except for no-inputs of the KaPR and the DPR dual-frequency products. TRMM/PR is a Ku-band radarand corresponds to the GPM/KuPR. We provide long-term homogeneous products, by applying
common processing algorithms in TRMM and GPM, as well as product format.

(4) Environment Auxiliary (ENV)
Environment auxiliary (ENV) is meteorological analysis data used as input data to the Level 2
processing, and same as that of the GPM/DPR, described in Section 3.2.1(4), except for no-outputs of
the KaPR and the DPR dual-frequency ENV products.

(5) Spectral Latent Heating Product
TRMM Spectral Latent Heating Product is same as that of the GPM/DPR, described in Section

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3.2.1(5) We provide long-term homogeneous products, by applying common processing algorithms in
TRMM and GPM, as well as product format.

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3.3. Calibration and Validation
The Global Precipitation Measurement Project (GPM) is an mission to measure global precipitation
using one GPM core satellite with the Dual-frequency Precipitation Radar (DPR) and the GPM
Microwave Imager (GMI) onboard and constellation of several other satellites with a microwave
radiometer (imager/sounder) onboard. The DPR consists of a Ka-band precipitation radar (KaPR) anda Ku-band precipitation radar (KuPR), and simultaneous measurements of KaPR and KuPR makes
possible to obtain accurate precipitation date including weak rainfall and snowfall. The Global Satellite
Mapping of Precipitation (GSMaP) is generated hourly from the combination of GMI and constellation
satellites. The purpose of GPM is to assess and predict the global water cycle variation, to contributeindustrial utilization, and to generate and disseminate these accurate, high frequent and constantproducts. To achieve this, accurate, uniform and stabilized for long term is required.
By the GPM calibration and verification, we keep data quality through the series of the works, likethe sensor test and construction of sensor model before launch, data evaluation in orbit, calibration,
precision evaluation of physical value especially rain rate, and to exposure the result of the evaluation
result after launch.

3.3.1. Calibration
The calibration of DPR decides the coefficient of the sensor model using in Level 1 algorithm by
the ground examination result and the data evaluation in orbit in cooperation with the sensor
development team. In the work, the experience in the TRMM/PR calibration is used and executed as
far as possible. The external calibration method is examined by considering dual frequency in addition
to improving to acquire insufficient information in the case of TRMM/PR calibration work through thereexamination of a ground test and an analytical item before launch. The result obtained from PR isreflected to the sensor model of the received power calculation. The calibration process, method andtools are prepared and performed efficiently based on the result of PR. It is necessary to prepare several
more efficient radar calibrators for DPR calibration.

(1) Outline of Calibration Plan
The outline of calibration is described in the “GPM/DPR Calibration Plan”. The calibration of DPR
consists of 3 operation phases, development phase before launch, initial checkout phase just after
launch, and nominal operation phase.

(2) Calibration Items① Initial Checkout Phase
The coefficient of the sensor model using in Level 1 algorithm is updated based on internal
calibration result in orbit and external calibration result in orbit using radar calibrator set in the ground.
The contents of the calibration are listed in Table 3.3-1. As the DPR has KuPR, KaPR dual frequency

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beam, the adjustable parameter to match the observation volume for the radar operation is optimized
and reflected to Level 1 algorithm.
Table 3.3-1 External Calibration and Internal Calibration
Mode
External
calibration

Contents
External calibration is performed when GPM passes over radar
calibrator set in the ground, and DPR is operated in an external
calibration mode which is different from a usual observationmode, and absolute calibration of transmitting power, theantenna pattern, and the received power etc. of DPR are
executed.

Internal
calibration

The measurement of the I/O characteristic of DPR is executedby using the internal loopback signal in SCDP (System Control
Data Processing) and FCIF (Frequency Converter / IF unit) of
DPR.

Measurement items
transmitting power andreceived power
antenna pattern foralongtrack direction andcrosstrack direction
beam matching between
KuPR and KaPR
the I/O characteristic of
SCDP and FCIF

② Nominal Operation Phase
The calibration in nominal operation phase decreases its frequency from initial checkout phase. After
this work, Level 1 algorithm is updated.
Table 3.3-2 Calibration in Nominal Operation Phase
Mode
External
calibration
Internal
calibration

Frequency
two seasons per year
(5 times per season)
approximately once
per week

Place
Pass over radar calibrator set point(around Tsukuba area)
When delta V maneuver performs, etc.

Duration
about 5 minutes
about 5–30 minutes

3.3.2. Validation
The validation of GPM products are conducted with the maximum use of the experiences on
TRMM/PR. Ground-based observation data, practical data obtained by meteorological or ocean
organization in various countries and data obtained in various scientific projects are used to the
maximum. From the experiences of TRMM/PR validation, needed is validation focusing on thealgorithm development. The long-term precipitation data by TRMM/PR are also used to the maximum.
The purpose of the validation is to improve the accuracies of products and meet the target accuracies
and success criteria in Table 3.3-3, by reflecting the results to level 2 and 3 algorithms.

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Table 3.3-3 Success Criteria of GPM/DPR Project
Mission requirement

estimate accuracy oflatitude distribution ofmonthly-averaged
globalprecipitation
amount:+/- 10% or smaller
Always-on observation
with
0.2
mm/hr
sensitivity from nonSun-synchronous orbit
with 65 degrees oforbital inclination

Minimum success(time to judge: 1 year
after the end of theinitial C/O)
Difference
between
DPR and AMeDAS on
domestic precipitation
amountaveragedthrough 12 months:
around +/- 10%
Always-on observation
with
0.5
mm/hr
sensitivity by KuPR or
KaPR

Full success(time to judge: end of
mission period [3years])
Difference
between
DPR and ground-basedrain gauges around theworld on long-term
average of precipitation
amount:+/- 10% or smaller
DPR meets functional
andperformancerequirements and canalwaysobserveprecipitation with 0.2
mm/hr sensitivity.

Extra success(time to judge: mission
end review)-

Beyond the mission
period, DPR meetsfunctional
andperformancerequirements and canalwaysobserveprecipitation with 0.2
mm/hr sensitivity.

(1) Outline of Validation Plan
The validation should be smoothly conducted by using the experiences on TRMM/PR. As theprecipitation changes, rapidly with time or place, it is not sufficient to simply compare theinstantaneous values of physical quantities between the satellite-mounted precipitation radar andground-based instruments including radar whose special observation objects are different from eachother in sizes and shapes. From this point of view, validations in GPM are conducted under thefollowing policies.


As well as end-to-end validation, the physics models supposed in the algorithms should be also
validated. It is helpful to make effective use of the results of ground validation experiment.

Super sites (in Okinawa, Sapporo, etc.) should be established, where observational instruments
are concentrated to obtain long-term data used for validations of physics models.



Data obtained from ground should be used rather than from airplanes.



By utilizing data of the observation network, long-term and wide-scope data should becompared.

As the approaches and measures are different from each other, the validations of GPM/DPR are
separated into algorithm validations and product validations. Algorithm validations are intended todevelop and improve the level 2 and 3 algorithms, and conducted continuously before the launch of
GPM core satellite. In product validations, products created by the level 2 and 3 algorithms arevalidated. Especially the accuracy of precipitation amounts is evaluated and check whether it meetsthe target accuracies and success criteria. The results of the accuracy evaluations in the productvalidations are provided to users (PI researchers, practical utilization organization, collaborative

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research organization and general researchers) and fed back to algorithm developers to improve theaccuracy of products. Compared with TRMM/PR, validations corresponding to higher accuracy andhigher sensitivity are needed for GPM/DPR. In other words, validations of weaker precipitation andsolid precipitations are needed. Regarding solid precipitation, amount estimation algorithm andvalidation method have not been established yet. Therefore, characteristics about snow should be
investigated first. From that point of view, starting algorithm validations before the launch is very
important.

(2) Product Validation
In product validations, standard products created by the level 2 and 3 algorithms are validated, andeventually it is checked whether the target accuracies and success criteria are met.
To reduce the sampling error and the error resulting from area characteristics, as long-term and widescope data as possible are used for product validations. The data collection and comparative validations
are conducted as below.


By using data compiled by TRMM/PR, TMI and GSMaP, statistical values (average, trend,
histogram, etc.) are compared.



By collecting existing steady observation data from AMeDAS, X-net, etc., statistical values(average, trend, histogram, etc.) are compared with reflection intensities and precipitation
amounts included in products created by level 2 and 3 algorithms.

The match-up data and long-term statistical values obtained from other satellite project, e.g.
GCOM-W/AMSR2 and EarthCARE/CPR, are used for comparative validation.



Under mutual cooperation with NASA GV team, steady local observation data around world
are collected and used for the product validations.



The validations are conducted under cooperation with Asian countries with a view to thepromotion of utilization (skill development and education).

Table 3.3-4 shows data used for the validation of each product. Validations described above areconducted for each product, and each algorithm is improved in accuracy. Eventually, it is evaluatedwhether the success criteria of GPM/DPR project are achieved.

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Table 3.3-4 Data Used for Validations of Standard Products
Level

Algorithm

L1

KuPR
KaPR
DPR

L2

L3

Product

Target forcalibration/validation
Received power

Data used forcalibration/validation
External calibration data,
Internal calibration data

KuPR
KaPR
DPR
DPR/GMI Combinedreflection intensity,
precipitation profile

DPR
DPR・GMI Combined

GroundamountGround-based radar (in Okinawa
and Sapporo),
X-net of National ResearchInstitute for Earth Science andDisaster Prevention (NIED),
Precipitation intensity from GMI,
Data from other satellites (GCOMW/AMSR2, EarthCARE/CPR, etc.)
AMeDAS, radar AMeDAS,
X-net of National ResearchInstitute for Earth Science andDisaster Prevention (NIED),
Precipitation intensity from GMI,
Data from other satellites (GCOMW/AMSR2,
EarthCARE/CPR,etc.),
Precipitation map products,
Rain gauge network,
Validation data from Asia

GSMaP

precipitation(3) Algorithm Validation
The algorithm validations can be divided into two main categories. The one is validation by groundbased observations. The other is validation by simulated data.

① Validation by Ground-based Observations
It is helpful in development and improvement of DPR, DPR/GMI combined and GSMaP algorithms
to validate errors on various parameters included within precipitation estimation algorithm related toattenuation by precipitation particles, distribution of diameters of raindrops, fall velocity and densityof snow, and so on. In order to achieve this purpose, it is now under consideration to introduce 2 ofground-based Ka-band radar, instead of using existing ground-based instruments.
The observation sites are established and operated, where observation instruments are concentrated
to obtain various parameters needed for the algorithms. As the ground-based observations describedabove are necessary for algorithm development, they are conducted before the launch of the coresatellite.

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GPM Data Utilization Handbook② Validation by Simulated Data
By using the reproduced nature based on data obtained from ground or that from numerical models,the forward calculations are conducted and simulated observation data (corresponding to L1: received
power and brightness temperature) are created. By comparing the results of L2 algorithm inputting thisdata with the reproduced nature, the algorithms are validated.

(4) Product Evaluation
In this section, the evaluation results pertaining to the requirements of data release are mentioned.

① DPR Level 2 productThe data accuracy requirement for data release is as follows:

The differential of radar scatter cross-section between KuPR and PR is less than ± 2 dB at sea
surface (1 month, no precipitation, and at the angle bins where the wind effect is negligible)The differential of radar scatter cross-section between KaPR and KuPR/PR is less than ± 2 dB
at sea surface (1 month, no precipitation, and at the angle bins where the wind effect isnegligible) considering the difference in radio frequencyThe ratio of rain intensity between KuPR and PR is less than 50% for 0.7 mm/h to 30 mm/h (2months, over ocean, ± 30° in latitude, all angle bin, and at surface)The ratio of rain intensity between KaPR to KuPR and KaPR to PR is less than 50% for 0.7
mm/h to 10 mm/h (2 months, over ocean, ± 30° in latitude, all angle bin, and at surface)The ratio of rain intensity between DPR and KuPR and DPR and PR is less than 50% for 0.7
mm/h to 30 mm/h (2 months, over ocean, ± 30° in latitude, all angle bin, and at surface)

Figure 3.3-1 is the radar cross-section calculated under the condition from the requirement for data
release. The results of differences at 5.3° of incident angle are 0.0 dB, 0.4 dB, and 0.2 dB for KuPRPR, KaPR (MS)-PR, and KaPR (HS)-PR, respectively, and thus DPR L2 products fulfilled the first andsecond requirements.
A formula to evaluate the ratio of rain amount between different sensors is defined as follows:
Ratio = |Sensor − PR|/(Sensor + PR) × 200 [%]Figure 3.3-2 shows the rain rate of zonal mean in a width of 5°in latitude over ocean and a ratio
under the condition as the requirement defines. The data period is 2 months, i.e., June 2014–July 2014.
When KaPR is compared with the inner swath of PR, the obtained average ratios are 1.9%, 11%, and2.9% for KuPR, KaPR (MS), and KaPR (HS), respectively. Thus, the DPR L2 products fulfilled therest of the requirements.

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Figure 3.3-1 (Left) the deviation of radar scatter cross-section; (right) monthly average andstandard deviation of radar scatter cross-section

Figure 3.3-2 Zonal mean of rain (Top) and Ratio(Bottom) in V05 product

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GPM Data Utilization Handbook② Combined Level 2 productThe data accuracy requirement for data release is as follows:

The error for the rain intensity of 1 mm/h is less than 50%, while the error for 10 mm/h is lessthan 25% at a horizontal resolution of 50 km.

Figure 3.3-3 (Left) the histogram of precipitation intensity; (right) the difference of rain frequency
The error at 1 mm/h rain rate is approximately ± 5% and that at 10 mm/h is approximately ± 15%.
Thus, the accuracy of the combined L2 product meets the release requirement.

③ GSMaP Level 3Global precipitation distribution and moving average of rain between GSMaP with GPM/GMI
and GSMaP without GPM/GMI is consistent. As this is to confirm GMI data as a new input,
this requirement should be verified at the first data release itself.



The average of root means square error to daily accumulated rain amount of Radar-AMeDAS
in 0.25° grid is less than 0.7 mm/h.

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Figure 3.3-4 Monthly accumulated rain amount of GSMaP with GMI and GSMaP without GMI(April 2014)

Figure 3.3-5 Time series of RMSE from July 1, 2014 to August 31, 2014. Daily value is represented
in dotted lines and 15-day moving average in solid lines
The consistency between “GSMaP with GMI” and “GSMaP without GMI” is clear as shown in
Figure 3.3-4. The difference for GSMaP_MVK is 0.97% and that for GSMaP_Gauge is 0.46%. Since

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the average values of RMSE for 2 months are 0.43 mm/h (GSMaP_Gauge) and 0.47 mm/h
(GSMaP_MVK), GSMaP meets the release requirement.

3.3.3. Calibration of TRMM
(1) External Calibration of TRMM PR
External calibration for TRMM PR had carried out about 10 to 20 times per year and it guaranteed
the stability of the observation through the operational period. Now, the new version 8 is released,
TRMM/PR calibration was reexamined with new knowledge obtained from experience in GPM/DPR’s
calibration.
Radar calibration is to determine the radar constant C in equation (1) through the measurement ofreceived power Pr by an active radar calibrator (ARC).
𝐶𝐶|𝐾𝐾𝑤𝑤 |2
𝑍𝑍𝑚𝑚 (𝑟𝑟)𝑟𝑟 2Here, C and Kw and other symbols are;
𝑃𝑃𝑟𝑟 (r) =𝜋𝜋 3 𝑐𝑐𝑐𝑐
𝑃𝑃 𝐺𝐺 𝐺𝐺 �𝜃𝜃 𝜃𝜃 𝜃𝜃 𝜃𝜃
210 𝜆𝜆2 ln 2 𝑡𝑡 𝑡𝑡0 𝑟𝑟0 𝑡𝑡1 𝑡𝑡2 𝑟𝑟1 𝑟𝑟2𝜖𝜖𝑟𝑟 − 1 𝑛𝑛2 − 1
Kw ==𝜖𝜖𝑟𝑟 + 2 𝑛𝑛2 + 2
𝑃𝑃𝑡𝑡: Transmitting power
𝐺𝐺𝑡𝑡0 、𝐺𝐺𝑟𝑟0: Antenna gain𝜃𝜃𝑡𝑡1、𝜃𝜃𝑡𝑡2、𝜃𝜃𝑟𝑟1 、𝜃𝜃𝑟𝑟2 : Beam widthλ: Wave lengthτ: Pulse widthc: Speed of light𝜖𝜖𝑟𝑟: Dielectric constant of water
C=

…(1)

…(2)
…(3)

Reexamination of external calibration consists of the updates of those parameters, pulse shape, anddefinition of pulse width and improvement of the beam mismatch correction. In addition, the antenna
gains and the calibration instruments and its technique was improved.
In consequence, reflectively factor (Zm) increased by about 1.1 dB from the PR V7. PR’s normalized
surface cross section (σ0) statistics shows good agreement with DPR’s σ0 by -0.02 dB during theoverlapping period.

(2) External Calibration of TRMM PR
A new parameter, adjustment factor is introduced in PR & DPR L2 PRE module to offer
homogeneous and continuous data between PR and DPR to detect the long-term variation of
precipitation. Base adjustment is 0.02 dB for σ0 and Zm, respectively to make PR’s σ0 and DPR’sσ0
exactly matching.

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Figure 3.3-6 Difference of PR’s σ0 and KuPR’ sσ0 in case of no precipitation(Left: PR V7 - KuPR V04, Right: PR V8 - KuPR V05.
There is underestimation of PR’s σ0 in outer angle due to the lack of oversampling.)
Addition to this, the minor calibration drift during TRMM operational period, a temporal adjustment
factor which has orbit number dependency is introduced. It varies from -0.23 to +0.27dB and cancel
the time-series of σ0 change.
As a result, stable TRMM PR V8 continues to KuPR V05 seamlessly.

Figure 3.3-7 Time series of σ0 under the condition of sea surface wind by microwave imagers is 8 m/s,
incident angle is 9 degrees, and atmospheric attenuation was corrected. PR is with TMI、KuPR iswith GMI. PR V8 b18 is comparable to V8. The data of sea surface wind was offered from Remotesensing systems. Figure by Dr. Kaya Kanemaru, AORI, University of Tokyo.

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GPM Data Utilization Handbook(3) Conditions
PR V8 L2 algorithm is comparable to GPM KuPR V05 except for sidelobe rejection routine and the
database for surface reference method. PR V8 still holds the effect of orbit transition (2001/08) and
FCIF switching (2009/06). Please note that the PR and KuPR are comparable at the calibration, but
their sensitivity is different.

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GETTINGIMAGESGPM

PRODUCTS

AND

This chapter introduces the services providing GPM products, images and related information.

4.1. Service Descriptions
As a general rule, GPM products are provided on the Internet. Research products, images, results ofapplication researches, operational information on the satellite and the sensors, and so on, as well as
standard products, are available from the website of JAXA and NASA. The services are listed in thefollowing table and described in detail in the subsections below.
Table 4.1-1 Services
Provided thing
Standard products
They are the products with the accuracy
assurance by JAXA or NASA. The nearreal-time products are treated as
equivalent to the standard products,
while between them there are somedifferences on the input auxiliary data or
the file coverage. See Chapter 3.
Research products
They are not accuracy-guaranteed, but
provided as they are useful.

Images and results of application
researches
They are created from data of GPM andother satellite, and show precipitation
amounts or typhoons in an easy-tounderstand way.
Operational information on the satellite
and sensors
The information regarding operation status anddata missing are provided.

Service
JAXA > G-Portal
https://gportal.jaxa.jp/gpr/
NASA > Precipitation Processing System (PPS)> Data Products Ordering Interface（STORM）
https://storm.pps.eosdis.nasa.gov/storm/

JAXA > Earth Observation Research Center > GPM
https://www.eorc.jaxa.jp/GPM
NASA > Precipitation Processing System (PPS)> Data Products Ordering Interface（STORM）
https://storm.pps.eosdis.nasa.gov/storm/
JAXA > Earth Observation Research Center > GPM
https://www.eorc.jaxa.jp/GPM/en/index.html
NASA > Precipitation Measurement Missions (PMM)
https://gpm.nasa.gov/

JAXA > G-Portal
https://www.gportal.jaxa.jp/
NASA > Precipitation Processing System（PPS）
https://arthurhou.pps.eosdis.nasa.gov/

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4.1.1. Getting Standard Products
The standard products are available from the data providing site of JAXA and NASA.
There are the common standard products between JAXA and NASA, as well as individual ones ofeach of them.
There are level 1, 2 and 3 common standard products. They are available from the website of JAXA
and NASA. The algorithms of the level 2 and 3 common products are jointly developed by JAXA andNASA. It is recommended to download them from the domestic, i.e. nearer, site, as it takes a long time
to download them from the overseas site due to the long roundtrip time (RTT). Please note that JAXA
and NASA publish a common product in different file names.
The individual standard products are provided only on each website of JAXA and NASA. As an
example of the individual products, JAXA and NASA provide the global precipitation map products
named “GSMaP” and “iMerge” respectively.
Please respect the copyright of the data when using them. See 4.1.5 for the usage note.

(1) JAXA G-Portal https://www.gportal.jaxa.jp/
The JAXA standard products are available from G-Portal, which is an earth observation data
providing system. You can cross-search and download earth observation data of JAXA, e.g. GCOMW, TRMM and ADEOS. You can refine your search by selecting the kind of physical quantities.
In the same manner as existing services, you can refine your search by specifying satellites, sensors,
geographical areas and dates. In addition to that, you can find data by specifying kinds of physicalquantities. That functionality is helpful for users not familiar with the satellite and sensors.
G-Portal provides the functionality of searching with specifying kinds of the physical quantity. See
Figure 4.1-1.
The data search functionality mentioned above is useful for users who want to get specified
geographical areas, periods or events like typhoons. The direct download functionality via FTP is also
provided for users who want to get a large amount of data at one time. See Figure 4.1-2.
You can directly get near-real-time products from the FTP server of G-Portal. Between near-realtime products and standard products, there are some differences on the input auxiliary data or the file
coverage in order to shorten latency for near-real-time products. See Figure 4.1-3. The near-real-time
products are removed from the FTP server after 7 days from the publication because the standard
products are published after about 3 hours to several days from the observation depending on kinds ofproducts.
Earth observation data are reprocessed along with improvement of calibration parameters and/or
processing algorithm. G-Portal provides basically latest version products, while it can provide theprevious version products by request from users.
G-Portal user manual (https://gportal.jaxa.jp/gpr/assets/mng_upload/COMMON/upload/GPortalU
serManual_en.pdf) for the usage of G-Portal, the procedure to create and register a public key, and so on.

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Figure 4.1-1 JAXA Standard Product Providing Service (G-Portal homepage)

Figure 4.1-2 G-Portal FTP Server

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Figure 4.1-3 Example of G-Portal FTP Direct Download(2) NASA STORM https://storm.pps.eosdis.nasa.gov/storm
The standard and research products of the precipitation measurement missions of NASA, i.e. GPM
and TRMM, are available from Data Products Ordering Interface (STORM) of Precipitation Processing
System (PPS).

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Figure 4.1-4 NASA Standard Product Providing Service (STORM homepage)

4.1.2. Getting Research Products
The research products are available from the data providing site of JAXA Earth Observation
Research Center (EORC) and NASA/PPS.

(1) JAXA Earth Observation Research Center (EORC) GPM
https://www.eorc.jaxa.jp/GPM/en/index.html
The research products of JAXA are available from EORC website.

Figure 4.1-5 Homepage of JAXA/EORC GPM Application and Research

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GPM Data Utilization Handbook(2) NASA STORM https://storm.pps.eosdis.nasa.gov/storm
On STORM, NASA/PPS provides the products which are treated as standard products in U.S., but
not agreed standard products of Japan and U.S.

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4.1.3. Browsing Images and Results of Application Researches
Dedicated tools or software are needed to visualize and/or analyze standard or research product ofearth observation data, which are HDF5 or binary format. You can get an image from JAXA/G-Portal,
after searching and selecting a product. In this subsection, introduced are websites where you can findimages easy-to-understand for the general users.
What data from satellites tell us and results of analyses are published on the websites as they come.

(1) JAXA Earth Observation Research Center (EORC) GPM
https://www.eorc.jaxa.jp/GPM/en/index.html
In “View observation data” “using observation data” menu of the site, you can find the links to GPortal, which provides the standard products, and that to “JAXA Global Rainfall Watch” page.

Figure 4.1-6 link to “View observation data” “using observation data”

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GPM Data Utilization Handbook(a) JAXA Global Rainfall Watch https://sharaku.eorc.jaxa.jp/GSMaP/index.htm
In this site, provided is the global distribution of rainfall derived from data of satellites. It is updated
every hour in near-real-time (about 4 hours after the observations). Using Google Map, you can easilychange focus from global to local.
You can browse overlaid images of rainfall distribution and cloud images observed fromgeostationary meteorological satellites for the specified date from past to current at will. You can also
see the rainfall distribution images of the latest 10 hours side-by-side and the animation of the transitionin the latest 24 hours. Furthermore, you can get the rainfall distribution in Google KMZ format anddisplay it on Google Earth if it is installed in your PC.

Figure 4.1-7 JAXA Global Rainfall Watch

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GPM Data Utilization Handbook(b) Tropical Cyclone Database and Real-Time Monitoring
https://sharaku.eorc.jaxa.jp/TYP_DB/index_e.html
https://sharaku.eorc.jaxa.jp/cgi-bin/typhoon_rt/main.cgi?lang=en
From Tropical Cyclone Database site, you can download data of tropical cyclones around the world,which are obtained by the earth observation satellites (GPM/DPR, GMI, TRMM/PR, TMI, VIRS,
GCOM-W/AMSR2, Aqua/AMSR-E and ADEOS-II/AMSR).

Figure 4.1-8 Tropical Cyclone Database
The images of tropical cyclones for the latest 2 weeks are available from Real-Time Monitoring site,
and the observation of GPM/DPR can verify precipitation images such as a typhoon and hurricane.

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Figure 4.1-9 Tropical Cyclone Real-Time Monitoring(2) NASA Precipitation Measurement Mission（PMM）

https://gpm.nasa.gov/

In “Science” and “Application” tabs of NASA/PMM site, images of GPM data are introduced withinterpretations.

Figure 4.1-10 NASA/PMM site

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4.1.4. Operational Information on the Satellite and Sensors
Depending on operational status of the satellite and the sensors, some of data are missing or unusable
for statistical processing from the point of view of quality. G-Portal and PPS provide users with theinformation on operational status and data missing.
If data in a file, i.e. an orbit, of GPM standard products are wholly missing or unusable from thepoint of view of quality, an “Empty Granule”, which includes only header information like observation
start/end time, are provided on G-Portal/SFTP server and PPS server. That allows users to distinguisherrors in downloads from data missing.
JAXA/G-Portal:

https://gportal.jaxa.jp/gpr/information/productNASA/PPS:

https://gpm.nasa.gov/data/news

Figure 4.1-11 Operational Information on the Satellite and Sensors
The mission concept, observation outline, product outline and format, analysis tools, user manuals,
and so on are introduced in websites of JAXA and NASA.
・The mission concept
JAXA/EORC: https://www.eorc.jaxa.jp/GPM/en/overview.html
NASA/PPS:https://gpm.nasa.gov/missions/GPM
・Product outline and format
JAXA/EORC: https://www.eorc.jaxa.jp/GPM/en/archives.html
NASA/PPS:https://pps.gsfc.nasa.gov/GPMprelimdocs.html

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・Analysis tools
JAXA/EORC: https://www.eorc.jaxa.jp/GPM/en/data_utilization.html
NASA/PPS:https://gpm.nasa.gov/data/tutorials

Figure 4.1-12 Links to Movies Introducing the Observation

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Figure 4.1-13 Link to the Format Specification and tools

4.1.5. Usage Note
GPM products and images provided on JAXA or NASA site are all copyrighted. You should becompliant with the terms of use.
The credits of the standard products are as below.
Kind of data
DPR, GMI and COMB
GSMaPCreditThe NASA/JAXA GPM project and the other
GPM Partners
JAXA

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UTILIZATION OF GPM/TRMM DATAIn this chapter, the outline features of the software tools to visualize or analyze GPM/TRMM data
are described, as well as the information to get them.

5.1. Data Visualization Tools
5.1.1. THOR
THOR (Tool for High-Resolution Observation Review) is a tool to visualize TRMM and GPM
products, developed by PPS (Precipitation Processing System) team in NASA.
With easy operations, it visualizes HDF-format data files in the forms of images, charts or texts. A
dataset in a product is displayed on the global map view. You can zoom in an area if you want. It canalso display a cross-section view parallel with or orthogonal to the path or at an altitude. Furthermore,
it provides a 3D view in the recent versions.
You can download this tool from the URL below.
For the usage, see the tutorial page below① Overview
https://arthurhou.pps.eosdis.nasa.gov/thorrelease.html② Tutorial
https://pps.gsfc.nasa.gov/THOR/version_2.2/tutorial.pdf③ Download and installation
https://gpmweb2https.pps.eosdis.nasa.gov/pub/THOR/
For your reference:
HDF manual: https://portal.hdfgroup.org/documentation/
HDF library installation: https://portal.hdfgroup.org/downloads/index.html

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file namemagnified view

selected dataset

swath on world map

Figure 5.1-1 Screen of THOR (KuPR example)

file nameselected dataset
magnified view

world map

Figure 5.1-2 Screen of THOR (GSMaP example)

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Figure 5.1-3 Screen of THOR (3D example)

5.1.2. HDFVIEWHDFVIEW is a tool to show data in HDF-format (HDF4 or HDF5) file.
This tool is developed with Java and runs under various OS, e.g. Linux, Windows and Macintosh.
Using it, you can easily look headers, or attributes, and rewrite data.
You can download this tool from the URL below.
https://portal.hdfgroup.org/downloads/index.html
For your reference:
HDF manual: https://portal.hdfgroup.org/documentation/index.html
HDF library installation: https://portal.hdfgroup.org/downloads/index.html

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Figure 5.1-4 Sample screen of HDFVIEW

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5.2. Data Analysis Tools
5.2.1. TKIO
TKIO (Science Algorithm Input/Output Toolkit) is a tool to read and write GPM and TRMM
products from Fortran or C code. It is developed by PPS (Precipitation Processing System) team in
NASA.
For the algorithm developers and researchers, it provides commonly used routines and constants,
contributing to reduce the code quantities for input/output implementation.
You can download this tool from the URL below.
① Overview
https://arthurhou.pps.eosdis.nasa.gov/gpmtoolkit.html② Download and installation
https://gpmweb2https.pps.eosdis.nasa.gov/pub/PPStoolkit/GPM/
For your reference:
HDF manual: https://portal.hdfgroup.org/documentation/index.html
HDF library installation: https://portal.hdfgroup.org/downloads/index.html

The procedure of the environmental setting, download and installation of TKIO are described here.

(1) Confirming the Environment for TKIO Installation
Linux (64bit if you want to use the writing capability)Perl 5 or higher



HDF5 version 1.8.6 or higher (PPS team recommends 1.8.9)



HDF4 version 4.2.7 or higher



ZLIB version 1.2.3 or higher (with libxml 2.6 to 2.7.6 for ZLIB 1.2.3 or lower, libxml 2.7.7 orhigher for ZLIB 1.2.4 or higher)

JPEG version 6b or higher



GZIP version 1.2.3 or higherMath Library 2.5 or higherC language: gcc or icc (Intel C Compiler)

Fortran: IntelⓇ Fortran Composer XE Linux edition

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GPM Data Utilization Handbook(2) Installing HDF5 Library (ver. 5-1.10.5 case)① Access to https://support.hdfgroup.org/ftp/HDF5/current/src/.
② Download the library for Linux (hdf5-1.10.5.tar.bz2).
③ Uncompress it.
$ tar –xjvf hdf5-1.10.5.tar.bz2④ Prepare for the installation.
$ cd hdff5-1.10.5$ ./configure –prefix=/xxx/xxx/xxx(/xxx/xxx/xxx: the directory where the library should be installed)$ make >&log_make.txt$ make check >& log_make_check.txt⑤ Install it.
$ make install(3) Installing TKIO (ver.3.60.2 case)① Access to https://gpmweb2https.pps.eosdis.nasa.gov/pub/PPStoolkit/GPM/tkio-3.60.2/ .
② Download the toolkit (tkio-3.60.2.tar.gz).
③ Place it in the directory where TKIO should be installed.
④ Uncompress it.
$ tar xvzf tkio-3.60.2.tar.gz⑤ Prepare for the installation.
$ cd tkio⑥ Set the environmental variables (for HDF4, HDF5, TKIO, compilers, flags, etc.).
See “(4) Setting the Environmental Variables” for details.
⑦ Compile and check.
$ ./INSTALL.pl compiler$ cd lib$ls
Libtkc.a libtkchdf4.a libtkchdf4algs.a libtkchdf5.a libtkchdf5algs.a
Libtkchelper.a libtkcselect.a libtkctkTSDIS.a(4) Setting the Environmental Variables
The following figures show how to set the environmental variables to use TKIO, in csh and bash

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case.
gcc case (libralies are installed in /home/tool/home/tool)

icc case (libralies are installed in /home/tool/home/tool)

Figure 5.2-1 How to Set the Environmental Variables in csh (left: gcc, right: icc)
icc case (libralies are installed in /home/tool/home/tool)

gcc case (libralies are installed in /home/tool/home/tool)

Figure 5.2-2 How to Set the Environmental Variables in bash (left: gcc, right: icc)

(5) Programming with TKIO
The procedure of programming using TKIO is described below.
① Including the header files
Write statements to include the header files provided by TKIO. There is a header file common
to all kind of products as well as dedicated to each sensor.
② Declaring variables of the input-output structure
Declare variables of the input-output structure defined in the TKIO header files. The names ofthe variables are your choice and used in the subsequent codes.
③ Opening a HDF file
Open a HDF file to be read.
④ Reading the metadata
Read each element of the metadata in the HDF file into a variable.
⑤ Reading data of each scan
If the file is one of GPM level 1 or 2 products, read the dataset for each scan.
⑥ Reading the grid data
If the file is one of GPM level 3 products, read all of the dataset at one time.
⑦ Closing the HDF file

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Close the HDF file and finish the data manipulation.

Figure 5.2-3 Procedure of Programming Using TKIO
From the other tools the users can use, h5dump and HDF Explorer are introduced below,

5.2.2. h5dump
h5dump is a command to read HDF5 files. It installed with HDF5 package. It provides thecapabilities to display in text format and to clip each element in binary format.
You can download this tool from the URL below.
https://portal.hdfgroup.org/downloads/
For your reference:
HDF manual: https://portal.hdfgroup.org/documentation/index.html
HDF library installation: https://portal.hdfgroup.org/downloads/index.html

5.2.3. HDF Explorer
HDF Explorer is a tool to show data in HDF (HDF4 or HDF5) files.

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You can download this tool from the URL below.
https://www.hdfeos.org/software/hdfexplorer.php
For your reference:
HDF manual: https://portal.hdfgroup.org/documentation/index.html
HDF library installation: https://portal.hdfgroup.org/downloads/index.html

5.3. File Format Conversion Tool
When HDF5 (Hierarchical Data Format 5) format is converted to the other format such as GeoTIFF,
KMZ format, NetCDF4 etc. under condition of user’s purpose and user’s analyzing tool, data can beused for more wider purpose. It is also expected to have much more opportunity in many areas.
HDF format is used for satellite numerical data. Because multidimensional arrays and database-liketables can be nested in HDF file. However, it is needed to install some soft wares or libraries for reading
HDF product, so it is too hard for the first-use researchers to use HDF products. (See Figure 5.3-1)
While, GeoTIFF format and KMZ format are useful and familiar for general user, which can behandled by general GIS software. Wider users as well as specific researchers get to use GPM productsin GeoTIFF or KMZ format by viewing, editing or analyzing the GIS information (precipitation rate or
statistics over map) by GIS software such as ArcGIS, QGIS, Google Earth and Image Viewers. (SeeFigure 5.3-2)
It is better for users, who is familiar with NetCDF4, to use NetCDF4-converted product rather than
HDF5.

Figure 5.3-1 GPM Data Handling without Format Conversion

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Figure 5.3-2 Expanding Data Utilization after Format Conversion

5.3.1. Earth Observation Satellite Data Format Conversion Tool
“Earth Observation Satellite Data Format Conversion Tool” is used to convert file format from HDF
which is used for GPM Level 3 products (DPR L3 daily, DPR L3 monthly, GSMaP hourly and GSMaP
monthly) into GeoTIFF and KMZ. This format conversion tool deal with not only GPM products but
also GCOM-W/AMSR2 product and JASMES product.
Users can download this tool from the following URL;
https://gportal.jaxa.jp/gpr/information/tool?lang=en
Utilization of GPM product converted in GeoTIFF or KMZ is introduced as below.
(1) Use by Viewers
GeoTIFF format file is readable as image data by popular viewers such as the Paint and the photoviewer.
This image data is easy for editing itself and uploading SNS.

Figure 5.3-3 Example of Viewing Precipitation Data by Viewers(2) Use by GIS Software
GeoTIFF format file can be handled by popular GIS software such as ArcGIS and QGIS. Using GIS
software functions, it is easily to refer the GeoTIFF precipitation data by mapping on world map, andto analyze and edit values of data.

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KMZ format file is used for Google Earth. The Google Earth application is a mapping applicationthat offers a bird’s-eye view of recorded locations across the globe, and precipitation data can be oneof layer.

Figure 5.3-4 Example of Mapping Precipitation Data on World Map

Figure 5.3-5 Example of Analyzing/Editing Precipitation Data by GIS software(3) Use for Web Service
GeoTIFF format file can be used as image data or numerical data, which can be input source data
for Web based service. There is possibility to use GPM precipitation data on web service for weather
prediction, disaster prediction, and so on.

Figure 5.3-6 Example of Weather Prediction Service and Disaster Prediction Service

5.4. Sample Program
Guidebook of sample programs (C, Fortran, and IDL) to use GPM Data will be available in the near
future. Japanese guidebook is available from below link;
https://www.eorc.jaxa.jp/GPM/en/data_utilization.html

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Appendix 1 ACRONYMS
A

Satellites

AAS： Automatic Alert System

APID： Application Process Identification

ASIST

： the
Web-accessible
system： APID Sorted Data

ASD
AMSR2

： Advanced Microwave ScanningRadiometer 2
The sensor carried by GCOM-W： Full SwathG

GPM： Global Precipitation MeasurementC

GMI： GPM Microwave Imager

G-Portal： JAXA Earth Observation Satellite
Data Distribution System： Goddard Space Flight Center： CCSDSFile Delivery Protocol

COMB

A protocol for file transmission
between satellites and groundsystems： Clouds and the Earth's RadiantEnergy System： Centre
National
dEtudes
SpatialesEtudes Spatiales
The national space laboratory ofFrance： Combined

CSH

Products derived from both DPR and
GMI： Convective Stratiform Heating： TRMM
Heating

FS

B： Active Radar Calibrator

CSHT： Frequency Converter • IF unit

： Global
ChangeMission 1st-Water“SHIZUKU”

ARC

CNES

FCIF

Satellite
Interface

GCOM-W1： Antenna Pattern Correction

CERES： EarthObservation
MissionExternal
GatewayF

monitoring

APC

CFDP

E-XING

Convective

Stratiform

GSFC
GSMaP

Mappingof

H
HDF： Hierarchal Data Format

HS： High sensibility beam ScanIICTICHARM
IDI
ISRO

D： Global Satellite
Precipitation

Observation

DOD： United States Department of Defense

DPR： Dual-frequency Precipitation Rader

DPS： Data Processing System

JAXA： Japan Aerospace Exploration Agency

E

JMA： Japan Meteorological Agency

EACH
EORC

： Earth observation Analysis Core andHub system： Earth Observation Research Center

EIS： EORC Information System

EUMETSAT ： European Organization for the
Exploitation of Meteorological

ITPS： Information and Communication
Technology： International Centre for Water
Hazard and Risk Management： Infrastructure
Development
Institute - Japan： IndianSpace
Research
Organization： Trend Analysis System
J

K
KaPR

： Ka-band Precipitation Radar

KuPR： Ku-band Precipitation RadarLLIS

APPENDIX 1-1： Lightning Imaging Sensor

GPM Data Utilization Handbook

LNA： Low Noise AmplifierM

MA： Multi-Access

MOC： Mission Operations CenterMS： Matched beam Scan

MWI

： MicroWave Imager

MWS： MicroWave Sounder

NASA
NOAA
NRT

： Tropical Rainfall Measuring Mission

TDRS： Tracking and Data Relay Satellite

TDRSS： Tracking and Data Relay Satellite
System
： TRMM Microwave Imager

TMI

U
N

NICT

TRMM

： National Institute of Information andCommunications Technology： National Aeronautics and Space
Administration： National Oceanic and Atmospheric
Administration： Near Real Time Data (Directory)UNIX： One of computer operation systems

URL： Universal Resource Locator
V

VIRS

W
WSC

O
P
PR

： Precipitation Radar

PRF： Pulse Repetition Frequency

PPS： Precipitation Processing System

PMM： Precipitation Measuring Mission
Q
R

RF： Radio Frequency
S

SCDP： System Control Data Processing

SDPS： Sensor data processing segment

SDIS

SDA

： Science Data processing andInformation Segment： GPM Science data Distribution
Segment： Science Data Archive

SFTP： SSH File Transfer Protocol

SLH

A SSH-based protocol to safely
transfer files between computers： Spectral Latent Heating

SLHT： TRMM Spectral Latent Heating

SSA： Single Service Access

SSPA： Solid-State Power Amplifier

STD： Standard

SDS：Visible and Infrared Scanner

T

APPENDIX 1-2： White Sands Complex
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Appendix 2 ASSOCIATED INFORMATION
A2.1 Reference Website
JAXA sites:(1) JAXA home page:https://global.jaxa.jp/(2) GPM/DPR page:https://global.jaxa.jp/projects/sat/gpm/(3) JAXA/EORC home page:https://www.eorc.jaxa.jp/en/index.html/(4) GPM home page (JAXA/EORC)
https://www.eorc.jaxa.jp/GPM/en/index.html(5) GPM/DPR special site:
https://www.satnavi.jaxa.jp/gpmdpr_special/(6) GSMaP home page:https://sharaku.eorc.jaxa.jp/GSMaP/index.htm(7) G-Portal home page:https://gportal.jaxa.jp/gpr/?lang=en
NASA sites:(1) NASA home page:https://www.nasa.gov/(2) GPM home page:https://gpm.nasa.gov/missions/GPM(3) PPS home page:https://arthurhou.pps.eosdis.nasa.gov/(4) PPS-STORM home page:https://storm.pps.eosdis.nasa.gov/storm/(5) HDF home page:https://portal.hdfgroup.org/

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A2.2 Contact information
Inquiries on this handbook:Satellite Applications and Operations Center (SAOC) Space Technology Directorate I
Japan Aerospace Exploration Agency (JAXA)
2-1-1, Sengen, Tsukuba, Ibaraki 305-8505, Japan
E-mail: GPM-MOS@ml.jaxa.jp

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Appendix 3

OVERVIEW OF GPM PRODUCTS■JAXA site：GPM (JAXA/EORC) https://www.eorc.jaxa.jp/GPM/index_e.htm
You can download the Release Note, Format Specification, Algorithm Theoretical Basis Document(ATBD), product list and overview of GPM product from the URL below.
https://www.eorc.jaxa.jp/GPM/en/archives.html

APPENDIX 3-1