Early provision of flood information byusing satellite monitoring data of GSMaPTetsuya IKEDA
Infrastructure Development Institute (IDI) – Japan
March 16, 2012
6th World Water Forum, Marseille, FRANCE
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Contents
1. Global Flood Alert System (GFAS) throughInternational Flood Network (IFNet)
2. GFAS development – Case study on Vietnam
3. Analysis of satellite precipitation data on theChao Phraya River basin
4. Conclusion and Way forward2

Background
Problems of hydrological observation and data collection
for flood warning and forecastingDifficulty to get real-time hydrological data on the river basin
Insufficient installation and maintenance of ground observatory stations
with real-time information network (rainfall, water level, flood discharge…).
Lack of data and model for flood warning and forecasting.
Limited budget and human resources for installation and maintenance ofobservatory station, flood warning and forecasting.
Insufficient framework to enhance technical skill and capacities.

-> Satellite monitoring can supplement and/or substituteground observation for flood warning and forecasting,applicable to anytime, anywhere of the world.
Rain gauge

Rain gauge
Rain gauge

No transmission
Rain gauge

Rain gauge

Rainfall observation by handOfficeImage Source : JAXA

IFNet (International Flood Network)
Background Rising trend of flood damages
 View of flood issues as locally limited problems
 Few networks that dedicated to flood issues
 Necessity to give priority to flood issues
IFNet was set up as an open network everyone
can join on the flood day of WWF3 in 2003.
Objectives
To contribute to flood disaster reduction by: Sharing knowledge and lessons, Promoting good practices, Raising awareness on flood risk among policy makers & citizen.
Membership IFNet is an open, free network to everyone, currently 617
registered from 81 countries (as of 31 March, 2010).
4 Advantage: Opportunity to receive GFAS information

GFAS (Global Flood Alert System)
1. Project Concept- Attempt to utilize satellite precipitation data for flood early warning- Support for existing flood early warning wherever necessary- Promoted both by Ministry of Land, Infrastructure and Transport(MLIT) and by Japan Aerospace Exploration Agency (JAXA)
2. Development through collaboration among:i) JAXA as satellite precipitation data providerii) IDI as system developer and operatoriii) IFNet as flood early warning transmission networkiv) Hydrological/ Meteorological Authorities, Disaster Management
Sections, and River Managers of any part of the world as users offlood early warning and forecasting, by supplementing and/or
substituting ground observatory stations of very limited numbers
5Schematic figure of GFASi) Space agencies
NASA Homepage

Heavy rainfall in theriver basin

Satellite observationii) IDI-Japan
Download of dataRiverSystem development

Data processingiv) Hydrological service
to river authorities

Mapping, EmailFlood warning and forecasting byusing GFAS Information etc.

iii) IFNet
1.
2.

IFNet Homepage
Email of heavy rain information
to IFNet members in charge offlood forecasting and warningv) Residents/
NGOs/
Communityleaders

6Website of IFNet & GFAS
Precipitation data of the world from satellite monitoring
GFAS website: http://gfas.internationalfloodnetwork.org/gfas-web/

Latest 1 day rainfall in theworld is displayed on theinitial page

You can select 1 or 3-day
rain fall from pull-downmenu here.
You can selectfrom 9 regions
Then, click here for display.

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GFAS : Enlarged maps for 9 regions of the world
Europe& North Africa
Middle East
South Africa
South Asia
Southeast Asia
East Asia
North America
South America
Oceania

Sample of regional map (South Africa)

8GFAS : Daily precipitation data - Example of Southeast Asia

Select 1 or 3-day rainfall
from pull-down menu

Latest 1 day rainfall
is displayed

Heavy rain area
Area with rainfall above 1/5
return period is shown by red.

9GFAS Up-grading 3B42RT >>> GSMaPTyphoon Ketsana on the Philippines (2009/09/26 daily)
3B42RT (1998-2008)

GSMaP (2007-)- Mesh size: 0.25°- data delay: 10 hours- Mesh size: 0.1°(10x10 km2)
- data delay: 4 hours

Up-grading from
3B42RT to GSMaP
enabled more detailed
and more rapidtransmission ofprecipitation data.

10GFAS for Ayeyarwady River in Myanmar
Heavy rain caused by Typhoon Nargis (using GSMaP data)

01 May 2008

Mawlamyaing(Moulmein)

02 May 2008

03 May 200804 May 2008

From any parts of the world,
hourly precipitation data ofany place (mesh) can beobtained even though groundobservations are not available.
11GFAS for Ayeyarwady River in Myanmar
http://gfas.internationalfloodnetwork.org/n-gfas-web/
 Available data

・maximum hourly rainfall data
within 24 hours
・1-day, 3-day or 1-week rainfall data Alert message by E-mailE-mail SAMPLE:

Heavy rain information to ZZ area at ---.
Mean basin precipitation of Ayeyarwady isXX mm/day. Please check on IFNet website!
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http://xxxxxxxxxxxxxxxxxxxxxx

GFAS Communicationfrom Tokyo

Alert mail(sample)

to Vietnam
Mua to tren 30mm/gio o vung thuongnguon luu vuc song Huong va song ThuBon.
Vao ngay trang web theo dia chihttp://gfas.internationalfloodnetwork.org/n-gfas-web/
Lien he van phong So NN&PTNT.

to Tokyo

Request mail(sample)

from Vietnam
Set up a new interface for **** City.
The alert is so frequent that you should reset the alertlevel as 50mm/h.

13

GFAS Development (1): Correlation between
satellite monitoring and ground observation
Satellite Monitoring

In order to estimate ground
precipitation, correlation
between satellite monitoringdata and ground precipitation
data has been studied.
ChinaHa Noi

Laos
Ha Tinh省
Quang Binh省

Ground observation

ThailandCambodiaViet Nam

Ho Chi Minh

Pilot study areas:
Huong Khe (Ha Tinh),
Mai Hoa (Quang Binh)10/11 01
10/11 07
10/11 13
10/11 19
10/12 01
10/12 07
10/12 13
10/12 19
10/13 01
10/13 07
10/13 13
10/13 19
10/14 01
10/14 07
10/14 13
10/14 19
10/15 01
10/15 07
10/15 13
10/15 19
10/16 01
10/16 07
10/16 13
10/16 19
10/17 01
10/17 07
10/17 13
10/17 19
10/18 01
10/18 07
10/18 13
10/18 19
10/19 01
10/19 07
10/19 13
10/19 19
10/20 01
10/20 07
10/20 13
10/20 19

Precipitation(mm/6hr)

10/11 0110/11 07
10/11 13
10/11 19
10/12 01
10/12 07
10/12 13
10/12 19
10/13 01
10/13 07
10/13 13
10/13 19
10/14 01
10/14 07
10/14 13
10/14 19
10/15 01
10/15 07
10/15 13
10/15 19
10/16 01
10/16 07
10/16 13
10/16 19
10/17 01
10/17 07
10/17 13
10/17 19
10/18 01
10/18 07
10/18 13
10/18 19
10/19 01
10/19 07
10/19 13
10/19 19
10/20 01
10/20 07
10/20 13
10/20 19

Precipitation(mm/6hr)

6-hours precipitation 2010/10/11-10/20

300

250

250
Huong Khe(Ground)
GSMaP_NRT

N20°200

150

100

50

N19°

0

Mai Hoa, Quang Binh (R=0.499)
Huong Khe(Ha Tinh)

Huong Khe, Ha Tinh (R=0.158)
N18°

300

Mai Hoa(Ground)
GSMaP_NRT200

Mai Hoa(Quang Binh)

150

100

N17°

50

0

N16°

E105°

Note: GSMaP_NRT data is the maximum one among the four mesh data. (□□）
E106°
E107°

3-days precipitation 2010/10/11-10/20
N20°

800
Huong_Khe(Ground)Precipitation(mm/3days)

700

GSMaP_NRT

600
500
400
300

N19°

200

Huong Khe(Ha Tinh)

10002010/10/13

2010/10/14

2010/10/15

2010/10/16

2010/10/17

2010/10/18

2010/10/19

2010/10/20

Huong Khe, Ha Tinh (R=0.881)

N18°

1200
Mai Hoa(Ground)Precipitation(mm/3days)

1000

Mai Hoa(Quang Binh)

GSMaP_NRT

800

N17°

600
400
200
0
2010/10/13

2010/10/14

2010/10/15

2010/10/16

2010/10/17

2010/10/18

2010/10/19

2010/10/20

N16°

Mai Hoa, Quang Binh (R=0.942)

E105°

Note: GSMaP_NRT data is the maximum one among the four mesh data. (□□）

E106°

E107°

Estimation of ground precipitationby using satellite monitoring data
correlation coefficient between ground data and satellite data
Huong Khe

Mai Hoa

6-hours precipitation

0.158

0.499

1-day precipitation

0.598

0.306

3-days precipitation

0.881

0.942

Ground precipitation can be estimated by using thesatellite monitoring data, considering the high correlation
coefficient of 3-days precipitation data.
800

800
Huong_Khe(Ground)y = 1.45x
R = 0.881

Precipitation(mm/3days)

700

Ground(mm/3days)

600

400

200

600

GSMaP_NRTGSMaP_NRT×1.45

500
400
300
200
100
000200400

600

GSMaP_NRT (mm/3days)

800

2010/10/13

2010/10/14

2010/10/15

2010/10/16

2010/10/17

2010/10/18

2010/10/19

2010/10/20GFAS Development (2): Estimation of probable
precipitation with return period (1/3, 1/5, 1/10…)
Pilot Areas :Huong Khe, Ca River Basin
Mai Hoa, Gianh River Basin
Ha Noi

China

Laos

Ca River28,000km2

ThailandCambodia

Viet Nam

Ho Chi Minh

Huong Khe

Mai Hoa

Gianh River
4,640km2

2-days and 3-days precipitation of10-years return period (1/10)
10Ca River
190mm/2days

70

100 150 200 250 300 (mm)Huong Khe

Mai Hoa

Gianh River
394mm/2days
363mm/2days

2-days precipitation

50Ca River
203mm/3days

Huong Khe

361mm/2days

20443mm/3days

Mai Hoa

Gianh River
437mm/3days
420mm/3days

3-days precipitation
Used Data:2003-2011 (9 years)

Utilization of probable precipitation
with return period for flood management
Probable 3-days precipitationof 1/3, 1/5, 1/30… of each river Probable precipitation (1/5, 1/10…) canbe calculated from GSMaP data (2003-11)

Ca RiverGianh River

1/3156 mm

252 mm

1/5

177 mm

317 mm

1/10

203 mm

420 mm

1/30

243 mm

633 mm…

…

…

Alert level can be examined,much better be testified byusing the ground observatory
data, if available

Flood Alert- Start of people’s evacuation- Preparation for flood defense activities

Recent topic: Flood in 2011 on Chao Phraya River
By using satellite-monitoring data from GSMaP, 3 month’s basinmean precipitation (July-September of 2008-2011) were analyzed
without using any ground observatory data.
2008

2009

2010

2011

527mm

710mm

Basin mean precipitation in Chao Phraya River Basin from July to September

518mm

424mm

Average(Bangkok)

DATA/ GSMaP MVK(2008)
GSMaP NRT(2009-2011)

0200 300 400 500 600 700 800 1,000 1,200(mm)Monthly precipitation of Chao Phraya River basin
200820092010

Average of3 years(2008-2010)

July

164mm

128mm

147mm

146mm

205mm
(140%)

August

164mm

151mm

217mm

177mm

225mm
(127%)

September

190mm

145mm

162mm

166mm

279mm
(168%)

Total rainfall
in 3 months

518mm

424mm

527mm

490mm

710mm
(145%)

2011(compared to 3years average)

More rain in July-August of 2011 than those of the previous threeyears, and much more rain in September.
At the end of August, we already knew the precipitation of this year
is bigger than the previous ones…
If we knew about this trend in advance, could we foresee today’sserious situation? or at least well prepared?

Conclusion and Way forward•

Ground observation need lots of time and huge cost for installation,
therefore satellite-monitoring precipitation can be supplemented
and/or substituted for flood management (warning and forecasting).

•GFAS can be applicable with good accuracy to relatively large-scaleriver basin and for long-term prediction.

•Still they need to develop and improve, so we want to invite morecountries/ organizations to participate in our activities through:- Collaborating on case study or pilot project for actual river basinof the world (in expectation of a little bit funds…)- Sending suggestion and useful comment through IFNet for further
improvement- Providing ground observation data to testify its accuracy

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Thank you very much for your attention
Merci beaucoup pour votre attention

ご清聴、ありがとうございました
清聴、ありがとうございました
Please contact to 2bu01@idi.or.jp:
IFNet: http://www.internationalfloodnetwork.org
GFAS: http://gfas.internationalfloodnetwork.org/n-gfas-web/24