Global Flood Alert System based on satellite derived rainfall data -Targeting the era of Global Precipitation Measurement (GPM)- Riko Oki, Misako Kachi (JAXA/EORC) Kazuhiko Fukami (PWRI) and Kazuo Umeda (IFNet/IDI) Asian Water Cycle Symposium 2-4 November 2005, Tokyo
Rainfall Measurement and Our Life Rain affects most everyone's life & work Food production Flood, drought Rain is a key variable in Weather prediction models Climate models Air-sea interaction models, etc. Rain is one of hardest meteorological parameters to measure, because of its spatial and temporal variability. Contribution by rainfall measuring satellites
Rainfall Observation by Precipitation Radar and Microwave Radiometer Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (active): Accurate measurement over land/ocean, fine spatial resolution, three-dimensional observation, narrow swath Microwave Radiometer (passive): Wide swath, carried by multiple satellites, worse estimate over land Radar and Cloud image 3-D Movie of PR Microwave Radiometer Super Typhoon CHABA(19W): Observed at 07:35Z 25 Aug. 2004 by TRMM
International Satellite Constellation 8 G TRMM PR,TMI GPM core DPR,GMI Megha-Tropiques Number of Satellites 7 6 5 4 3 M P DMSP SSM/I AQUA AMSR-E ADEOS-II AMSR DMSP SSMIS FY-3 (China) EGPM NASA GCOM-W NPOESS-C3 CMIS 2 1 DMSP SSM/I DMSP SSM/I DMSP SSMIS DMSP SSMIS NPOESS-C2 CMIS NPOESS-C1 CMIS Year 88 90 92 94 96 98 00 02 04 06 08 10 12 14 16 18
Outline of Global Precipitation Measurement (GPM) Core Satellite Dual-frequency Precipitation Radar Microwave Radiometer Observation of rainfall with more accurate and higher resolution Adjustment of data from constellation satellites Constellation Satellites 8 Satellites with Microwave Radiometers More frequent Observation JAXA (Japan) Dual-frequency Precipitation Radar NASA(US) Satellite Bus, Micro-wave Radiometer Cooperation :NOAA(US), NASA(US), ESA(EU), CNES/ISRO(France/India) and others Global Observation every 3 hours
Global Precipitation Map Currently, three-hourly rainfall products using present microwave radiometers and geo-ir data. In GPM era, there is a constellation of satellites in polar orbit, each carrying microwave radiometer provided by international partner. GPM will implement high-frequency (every three hours) global precipitation measurement. TRMM 3B42: Three-hourly merged rainfall at 12Z Jan. 29, 2002
Scheme of Global Flood Alert System (GFAS) Rainfall information Observation Satellites Heavy rainfall around In the XX river basin Data Acquisition Data processing Data Dissemination IDI-Japan System Development River 1. IFNet Homepage: Map (Heavy Rain Area), Mesh Data 2. Email Delivery of Heavy Rain: to IFNet members in charge of Flood Forecasting and Warning Around the downstream of river Flood Forecasting and Warning referring to GFAS Information
Objectives of GFAS To support flood forecasting and warning by providing near real-time satellite rainfall information and heavy rainfall area indication. Applicability of Satellite Data Satellite-derived rainfall data is considered to be informative especially under the following conditions: For large river basins without any telemetry systems Trans-boundary Rivers where prompt data transmission between countries is difficult.
Global Flood Alert System (GFAS) Current System Outline Rainfall Data: Global observation by Satellites Data source: TRMM data from Global Real-Time 3-Hourly Precipitation Analyses by NASA (3B42RT) Outputs: Delivery: 1. Rainfall map and text data (0.25 deg. grid in the band 0-360 deg. E., 60-60 N-S) 2. Probability analysis for daily rainfall (1/5, 1/10 chance) 3. Indication of heavy rain area (excessive rainfall area map) 4. E-mail delivery of heavy rainfall notice (on request) IFNet Website http://www.internationalfloodnetwork.org Actual Start: Early 2006
1. Rainfall information GFAS Information to be Delivered through IFNet Daily Rainfall Map (0.25 deg. Grid in the band 0-360 deg. E., 60-60 N-S, Global and Regional enlarged view) Daily Rainfall Data in text (0.25 deg. Grid in the band 0-360 deg. E., 60-60 N-S) Data source: TRMM DATA from Global Real-Time 3-Hourly 3 Precipitation Analyses (3B42RT) by NASA
GFAS information to be delivered 2. Probability analysis for daily rainfall (1/5 or 1/10) Map showing daily precipitation categorized by return period (Accumulated data for calculation; TRMM 3B42RT Jan.1998 Dec.2004) 3. Indication of heavy rain area (1/5 or 1/10) Map showing areas of daily precipitation exceeding 5-year and 10- year return period 4. E-mail delivery of heavy rainfall notice -on request- Sending notice e-mails to registered agencies when a rainfall over certain threshold is observed.
Visions for the Future (Cooperative Research at Public Works Research Institute) Satellite-derived Precipitation Runoff calculation Globally available Database: DEM, Land use, etc. Probable inundated area WATER LEVEL 水位 TIME 時間 A runoff calculation is performed using data through GPM after runoff model based on global mapping data is developed. This calculation will make it possible to forecast not only discharge and water level but also inundating state of flood at representative spots. The forecasting result obtained through the runoff calculation will be used for flood warning as well as various river managements such as flood control and water resources management. Water Resources Management Flood Control Management Flood Warning System
An example of runoff simulation with satellite-derived rainfall data Pakse, Mekong River (A=545,000km 2 (GRDC)) Hydrologic model: BTOPMC model of Yamanashi Univ., Japan Q ( m3/s ) 80,000 70,000 60,000 50,000 40,000 30,000 20,000 10,000 0 Qsim(3B42V5) Qsim(3B42V6) Qsim(Ground Rainfall) Qobs(monthly) Jan Feb Mar Apr May Jun Jul 1998 Aug Sep Oct Nov Dec
Thank you for your attention! Regarding IFNet-GFAS, please contact with IFNet Secretariat: E-mail: infor@internationalfloodnetwork.org http://www.internationalfloodnetwork.org