Overview ofGlobal Satellite Mappingof Precipitation (GSMaP)
Misako KACHI
Earth Observation Research Center (EORC)
Japan Aerospace Exploration Agency(JAXA)

16 March 2012 @ Side Event at the Japan Pavilion on the 6th World Water ForumToday’s Rainfall Distribution in the World
Rainfall and clouds in 00Z 16th March 2012 by GSMaP_NRT

I got this picture from our web site at 05Z of Today.

Precipitation Characteristics Observedby the Space Borne Instruments(a) Precipitation radar:• Back scattering from rain drops• High accuracy• Narrow swath widthTyphoon MORACOT (8 Aug. 2009) by TRMM

(a)

(b)

(c)

(d)

(b) Infrared radiometer:• Cloud top information• Not related to surface rain rates(c) Microwave imager (19V):(d) Microwave imager (85V):• Directly measures emission
from rainfall & scattering fromsnow/ice over the ocean• Directly measures scatteringfrom snow/ice over the land

It is important to combine the data from different frequencies
to retrieve precipitation

Production of “GSMaP” from Multi-satellite Data
GSMaP: Global Satellite Mapping of Precipitation

TRMM
TMIAqua
AMSR-EDMSP
SSM/I, SSMISNOAA&MetOp
AMSU-A/MHS
Geostationary
Satellite

Rain models
developedfrom PR
observations

Rainfall data retrieved
from each microwave
imager and/or sounderHourly merged microwave
rainfall map

Calculate cloud
moving vectors

GSMaP rainfall
in 0.1-deg gridand hourlyWhy We Need “Multi” Satellite Data?

GSMaP and JAXA “Global Rainfall Watch”
GSMaP
Originally funded by JST/CREST during 20022007, and by JAXA 2007-present.
MRI, Osaka Univ., Kyoto Univ., Univ. Tokyo

Near-real-time version of GSMaP (JAXA
Global Rainfall Watch) is distributed via
internetBinary and text data has been available sinceOct. 2008 via password protected ftp site.
Recently introduced
SSMIS (F16, F17) since Jun. 2010.
AMSU-A/MHS (N19, MetOp-A) since Aug. 2011.
AMSU-A/B (N15, N16) and AMSU-A/MHS(N18) is in preparation

3-hourly animation of three
Reanalysis data from Mar. 2000 - Nov.
typhoons (No.17-19) in2010 has been available since March 2012. 2009 by GSMaP_NRT.

JAXA/EORC Global Rainfall Watch
1-8 August 2011 (6-hourly) - Typhoon No.9 in 2011 “MUIFA” can beseen near Okinawa, Japan.

0.1-deg and hourly global rainfall productavailable 4-hour after observation via internet.
http://sharaku.eorc.jaxa.jp/GSMaP/GSMaP Accumulated Rainfall Amountover Thailand during Jun-Sep 2011

Chiang Mai(18.8N, 99E)
[Rain Gauge:921mm]

Bangkok(13.75N, 100.5E)[Rain Gauge:1251mm]

Vientian(18N, 102.6E)[Rain gauge:1641mm]

Phnom Penh
(11.55N,104.9E)
Accumulated rainfall
amount by GSMaP_NRT
was similar to those by raingauges at Bangkok, Chiang
Mai, and Vientian, provided
by JMA .Comparison to Rain Amount in 2010
Accumulated rainfall amountduring Jun-Sep 2010

Ratio of R2011/R2010
during Jun.-Sep.

International Precipitation Working Group(IPWG) Validation Program
Continental-scale validation (single number for entiredomain) of satellite-based rainfall map
Some sites include NWP output rainfall as “data”

Performed on daily totals
12 – 12 UTC – N. America, S. America, Western Europe
00 – 24 UTC – Australia, Japan

Performed on 0.25-degree grid box
Statistics and maps disseminated via web pages
Rain gauge & radar (some) used as “truth”
Currently 5 active validation “sites”
N. America, S. America, W. Europe, Australia, Japan
http://cawcr.gov.au/bmrc/SatRainVal/validation-intercomparison.html

Japanese IPWG Validation Site by Kyoto Univ.
http://www-ipwg.kugi.kyoto-u.ac.jp/IPWG/sat_val_Japan.html
Example :Heavy rain in 14 Jul 2010

Radar
AMeDAS

GSMaP_NRTCMORPH

MWCOMB

3B42RT

3B41RT

3B40RT

7/14

Collaboration with Flood Forecast/Warning
Communities
JAXA, ICHARM, and IFNet/IDI have studied possible application ofsatellite rainfall information to flood warning/forecast since 2003.
GFAS operated by IFNet/IDI, and IFAS distributed by ICHARM use
GSMaP and TRMM data as input rainfall data, and will contributeto flood forecast and early warning in poorly-gauged river basins.

GSMaP Data Utilization in Asian Countries (1/2)
GPM Asia Workshop
Held every year in Japan since 2004, inviting 5-10
meteorological, hydrological or remote sensing agencies inAsian countries who are interesting in satellite precipitation.
Promote satellite precipitation data utilization in Asia.
Utilization of GSMaP and/or TRMM data and their comparison
with ground-based data have started in Vietnam, Bangladesh,Philippines, Lao PDR, ICIMOD, Thailand, Indonesia, etc.

The 3rd GPM Asia Workshop on Precipitation Data Application Techniques, 7 & 9 Dec. 2011, Tokyo

GSMaP Data Utilization in Asian Countries (2/2)
Following projects related to GSMaP are ongoing under
JAXA and Asian countries. These projects focus on flood
including river basin management and landslide (shortterm events, debris flows, slope failures, etc).
ADB Technical Assistance - ‘Applying Remote Sensing
Technology in River Basin Management’Bangladesh, Vietnam, Philippines

THEOS Series and ALOS Series Cooperation
ThailandSentinel Asia Success Story in the Philippines

Global Precipitation Measurement (GPM)
GPM Core Observatory and constellation of satellites will collaborate to realize
global precipitation frequent observation with high accuracy.
Dual-frequency Precipitation Radar (DPR) will calibrate GPM Microwave Imager(GMI), and GMI will calibrate microwave imagers and/or sounders onboard
constellation satellites.
Constellation Satellites
Objectives:
ü Observation frequency
ü Science, social applications• Cooperation withconstellation providers; JAXA(GCOM-W), NOAA (JPSS),
CNES/ISRO (MeghaTropiques) etc.
• 3 hourly observation of 80%of the globe.
• Launch around 2012-2015 byeach organization• Mainly sun-synchronousorbit with altitude
600~800km

image by NASA

Core Observatory
Objective:ü Understanding the horizontal andvertical structure of precipitation
systemü Drop size distribution
measurement
ü Improvement of precipitation rateaccuracy with constellation
satellites• DPR (JAXA, NICT) (13.6, 35.5GHz)• GMI (NASA)• Launch in JFY 2013 by H-IIA rocket• Non-Sun-synchronous orbit,
inclination: 65deg, altitude: 407km

Generation and dissemination of global map of precipitation ratewith high frequency and accuracy

Summary
Production of GSMaP and GSMaP_NRTJAXA and collaborative organizations has developed precipitation product,GSMaP, and distributed its near-real-time version 4-hrs after observation inhourly and 0.1-degree grid box. Reanalysis data of past period is also available.
Rainfall retrievals from available MWRs are merged, and moving vector
information from five GEO IR data with Kalman filtering techniques is combined
to fill temporal gaps

Validation of multi-satellite productsInternational Precipitation Working Group compares various multi-satellite
products in a same manner at five active sites, including North America, SouthAmerica, Eastern Europe, Australia and Japan.
Japanese site operated by Kyoto Univ. in collaboration with JAXA to comparewith JMA’s Radar-AMeDAS (gauge calibrated radar rainfall).

Collaboration with flood community and Asian countries
JAXA collaborates with ICHARM and IFNet/IDI in utilization of satellite rainfall
data in flood warning/prediction.
JAXA also promotes GSMaP data utilization in Asia

JAXA will continue and enhance production of GSMaP and collaborative
activities toward GPM - Global Precipitation Measurement