Utilization of satellite precipitation data for flood management

Utilization of satellite precipitation data for flood management Tetsuya IKEDA Infrastructure Development Institute (IDI) Japan Typhoon Committee Integrated Workshop November 7, 2011 Nha Trang, Vietnam, 1

Contents 1. Global Flood Alert System (GFAS) by using International Flood Network (IFNet) 2. GFAS development Case study on Vietnam 3. Analysis of satellite precipitation data on the Chao Phraya River basin 4. Integrated Flood Analysis System (IFAS) developed by ICHARM 5. Conclusion and Way forward 2

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 of observatory station, flood warning and forecasting. Insufficient framework to enhance technical skill and capacities. -> Satellite monitoring can supplement and/or substitute ground observation for flood warning and forecasting, applicable to anytime, anywhere of the world. No transmission Rainfall observation by hand Image Source : JAXA

Background IFNet (International Flood Network) 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). Advantage: Opportunity to receive GFAS information 4

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 provider ii) IDI as system developer and operator iii) IFNet as flood early warning transmission network iv) Hydrological/ Meteorological Authorities, Disaster Management Sections, and River Managers of any part of the world as users of flood early warning and forecasting, by supplementing and/or substituting ground observatory stations of very limited numbers 5

Schematic Figure of GFAS i) Space Agencies NASA Homepage Observation Satellites Heavy rainfall around In the some river basin ii) IDI-Japan Data Download Data Processing Mapping, Email System Development River iv) Hydrological Service River Authorities iii) IFNet Flood warning and forecasting using GFAS Information etc. 1. IFNet Homepage 2. Email of Heavy Rain to IFNet members in charge of Flood Forecasting and Warning v) Residents/ NGOs/ Community leaders

Precipitation data of the world by using satellite monitoring You can select 1 or 3-day rain fall from pull-down menu here. Latest 1 day rainfall in the world is displayed on the initial page You can select from 9 regions Then, click here for display. 7

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. 8

GFAS Up-grading 3B42RT >>> GSMaP Typhoon Ketsana on the Philippines (2009/09/26 daily) 3B42RT (1998-2008) - Mesh size: 0.25 - data delay: 10 hours GSMaP (2007-) - Mesh size: 0.1 (10x10 km 2 ) - data delay: 4 hours Up-grading from 3B42RT to GSMaP enabled more detailed and more rapid transmission of precipitation data. 9

GFAS for Ayeyarwady in Myanmar Heavy rain caused by Typhoon Nargis (using GSMaP data) 01 May 2008 02 May 2008 03 May 2008 Mawlamyaing (Moulmein) 04 May 2008 From any parts of the world, hourly precipitation data of any place (mesh) can be obtained even though ground observations are not available. 10

GFAS for Ayeyarwady 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-mail E-mail SAMPLE: Heavy rain information to ZZ area at ---. Mean basin precipitation of Ayeyarwady is XX mm/day. Please check on IFNet website! http://xxxxxxxxxxxxxxxxxxxxxx 11

GFAS Communication from Tokyo to Vietnam Alert mail (sample) Mua to tren 30mm/gio o vung thuong nguon luu vuc song Huong va song Thu Bon. Vao ngay trang web theo dia chi http://gfas.internationalfloodnetwork.org /n-gfas-web/ Lien he van phong So NN&PTNT. to Tokyo from Vietnam Request mail (sample) Set up a new interface for **** City. The alert is so frequent that you should reset the alert level as 50mm/h. 12

GFAS Development (1): Correlation between satellite monitoring and ground observation Satellite Monitoring In order to estimate ground precipitation, correlation between satellite monitoring data and ground precipitation data has been studied. Ha Noi China Ground observation Laos Thailand Ha Tinh Quang Binh Cambodia Viet Nam Ho Chi Minh Pilot study areas: Huong Khe (Ha Tinh), Mai Hoa (Quang Binh)

6-hours precipitation 2010/10/11-10/20 300 250 Huong Khe(Ground) GSMaP_NRT N20 Precipitation(mm/6hr) 200 150 100 50 0 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 Huong Khe (Ha Tinh) N19 Huong Khe, Ha Tinh (R=0.158) N18 Precipitation(mm/6hr) 300 250 200 150 100 50 Mai Hoa(Ground) GSMaP_NRT Mai Hoa (Quang Binh) N17 0 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 Mai Hoa, Quang Binh (R=0.499) E105 E106 E107 N16 Note: GSMaP_NRT data is the maximum one among the four mesh data. (

1-day precipitation 2010/10/11-10/20 600 500 Huong_Khe(Ground) GSMaP_NRT N20 Precipitation(mm/day) 400 300 200 100 0 2010/10/11 2010/10/12 2010/10/13 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) N19 Huong Khe, Ha Tinh (R=0.598) N18 Precipitation(mm/day) 600 500 400 300 200 Mai Hoa(Ground) GSMaP_NRT Mai Hoa (Quang Binh) N17 100 0 2010/10/11 2010/10/12 2010/10/13 2010/10/14 2010/10/15 2010/10/16 2010/10/17 2010/10/18 2010/10/19 2010/10/20 Mai Hoa, Quang Binh (R=0.306) E105 E106 E107 N16 Note: GSMaP_NRT data is the maximum one among the four mesh data. (

3-days precipitation 2010/10/11-10/20 Precipitation(mm/3days) 800 700 600 500 400 300 200 100 0 Huong_Khe(Ground) GSMaP_NRT 2010/10/13 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) N20 N19 Huong Khe, Ha Tinh (R=0.881) N18 Precipitation(mm/3days) 1200 1000 800 600 400 200 Mai Hoa(Ground) GSMaP_NRT Mai Hoa (Quang Binh) N17 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 Mai Hoa, Quang Binh (R=0.942) E105 E106 E107 N16 Note: GSMaP_NRT data is the maximum one among the four mesh data. (

Estimation of ground precipitation by 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 the satellite monitoring data, considering the high correlation coefficient of 3-days precipitation data. Ground(mm/3days) 800 600 400 200 y = 1.45x R = 0.881 Precipitation(mm/3days) 800 700 600 500 400 300 200 Huong_Khe(Ground) GSMaP_NRT GSMaP_NRT 1.45 100 0 0 200 400 600 800 GSMaP_NRT (mm/3days) 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

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 Thailand Ca River 28,000km 2 Cambodia Viet Nam Ho Chi Minh Huong Khe Mai Hoa Gianh River 4,640km 2

6-hours and 1-day precipitation of 10-years return period (1/10) 10 20 50 70 100 150 200 250 300 (mm) Ca River 66 mm/6hr Ca River 143 mm/1day Huong Khe 131 mm/6hr Gianh River Mai Hoa Huong Khe 269 mm/1day 126 Gianh River mm/6hr 115 mm/6hr 264 mm/1day Mai Hoa 284 mm/1day 6-hours precipitation 1-day precipitation Used Data:2003-2011 (9 years)

2-days and 3-days precipitation of 10-years return period (1/10) 10 20 50 70 100 150 200 250 300 (mm) Ca River 190 mm/2days Ca River 203 mm/3days Huong Khe Huong Khe 361 mm/2days 443 mm/3days Mai Hoa Mai Hoa Gianh River 394 mm/2days Gianh River 437 mm/3days 363 mm/2days 420 mm/3days 2-days precipitation 3-days precipitation Used Data:2003-2011 (9 years)

Utilization of probable precipitation with return period for flood management Probable 3-days precipitation of 1/3, 1/5, 1/30 of each river Ca River Gianh River Probable precipitation (1/5, 1/10 ) can be calculated from GSMaP data (2003-11) 1/3 156 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 by using 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 Basin mean precipitation in Chao Phraya River Basin from July to September 518mm 424mm 527mm 710mm DATA/ GSMaP MVK(2008) GSMaP NRT(2009-2011) Average(Bangkok) 0 200 300 400 500 600 700 800 1,000 1,200(mm)

Monthly precipitation of Chao Phraya River basin 2008 2009 2010 Average of 3 years (2008-2010) July 164mm 128mm 147mm 146mm August 164mm 151mm 217mm 177mm September 190mm 145mm 162mm 166mm Total rainfall in 3 months 518mm 424mm 527mm 490mm 2011 (compared to 3 years average) 205mm (140%) 225mm (127%) 279mm (168%) 710mm (145%) More rain in July-August of 2011 than those of the previous three years, 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 s serious situation? or at least well prepared?

IFAS (Integrated Flood Analysis System) Ownership of local users in Developing Countries Global observation of rainfall by earth observation satellites Satellite-based near real-time rainfall data Topographic data Other GIS data for runoff mode (Land use, soil, etc.) Ex.) IFNet-GFAS, NASA- 3B42RT, JAXA-GSMaP Data download through Internet, free of charge Flood disaster prevention & mitigation Current situation Despite of the needs for flood forecasting/warning, No rainfall, GIS data, nor analytical tools Required much money & time for implementation After the application of IFAS: Prompt & efficient implementation No need to develop original core system Step-by-step improvement of accuracy with hydrological observational network

IFAS-based runoff analysis: Sendai River, Japan Discharge (m 3 /sec) 4,000 3,500 3,000 2,500 2,000 1,500 1,000 500 0 Good accuracy Ground-gauged rainfall Satellite rainfall(3b42rt) (original GSMaP) (corrected GSMaP) Calculated discharge(ground) (3B42RT) (original GSMaP) (corrected GSMaP) Measured discharge 9/6 9/7 9/8 9/9 9/10 Date (2004,GMT) 0 20 40 60 80 100 Rainfall (mm/hour) Onobuchi L=137km A=1,600km 2 Parameters are calibrated using ground-gauged rainfall and measured discharge product Wave shape error E W Volume error E V Peak discharge error E P Ground-based rainfall 0.030-0.021 0.030 satellite(3b42rt) 0.052 0.232 0.452 satellite(original GSMaP) 0.186 0.582 0.851 Satellite(corrected GSMaP) 0.029-0.026-0.035

Dissemination of IFAS ICHARM Development of IFAS Improvement of IFAS Toolkit for flood forecasting system (IFAS) Lecture, Training Request of improvement LOCAL USER Observation, data collection Implementation of flood forecasting system through customization of IFAS Flood forecasting and alert Reduction of flood risk Validation, damage Application results Local data Alert LOCAL SITE Residents

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 & IFAS can be applicable with good accuracy to relatively large-scale river basin and for long-term prediction. Still they need to develop and improve, so we want to invite more countries/ organizations to participate in our activities through: - Collaborating on case study or pilot project for actual river basin of 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 27

Thank you very much for your attention Please contact to 2bu01@idi.or.jp: IFNet: http://www.internationalfloodnetwork.org GFAS: http://gfas.internationalfloodnetwork.org/n-gfas-web/ IFAS: http://www.icharm.pwri.go.jp/research/ifas/index.html 28