HYDROLOGICAL ASPECTS Concerning The GCM/RCM INTERNATIONAL WORKSHOP THE DIGITIZATION OF HYSTORICAL CLIMATE DATA, THE NEW SACA&D DATA BASE AND CLII IN THE ASEAN REGION 02-05 APRIL, CITEKO – BOGOR, INDONESIA Dr. William M. Putuhena Experimental Station for Hydrology and Water Management RESEARCH CENTER FOR WATER RESOURCES MINISTRY OF PUBLIC WORKS Mechanism of global warming and climate change Large volumes of greenhouse gas emissions cause CO2 concentration in the air, increase heat absorption, and result in temperature rise, i.e. global warmings. Melting of glaciers, ice caps and ice sheets Thermal expansion of sea water Change in evapotranspiration Change in snow accumulation condition Sea level rise More intense typhoons Increase of precipitation More frequent heavy rains and droughts Earlier snow melt and reduction of discharge Change in water use pattern Increase of river flow rate More frequent storm surges and coastal erosions More frequent floods More serious sediment disasters Higher risk of drought Source: Okada, 2008 To provide a comprehensive understanding of the climate change impact on water resources Two Modeling Systems 1. Climate Model (GCM/RCM) 2. Hydrological Model Global Climate Models Hydrological Models Target Event to Continuous Model Lumped to Distributed Model Conceptual to Physical Model B Model D O W N S C A L I N G Global Climate Regional Climate Local Climate 6 Hydrological Modeling Data Climate Change Information Water resources condition in the future Design Rainfall Current Design Rainfall Design Hydrograph Future Design Rainfall under Climate Change Discharge (m^3/s) 1 Hydrological Model Climate Change Current Climate T Existing Gaps Between GCMs ability and Hydrology Need Some Models Resolution Created By Australia Spatial Scales Mismatch Temporal Scales Mismatch Temporal Scales GCMs Hydrological Model GCMs Ability Declines Hydrological Importance Increases Seasonal Annual Monthly Daily Hourly Minute Data Feed NWP Satellite Radar Telemetry accuration decreases Lead Time River discharge Flood Time Present condition Flood forecasting Detections Run-off analysis Warning Response Vertical Scales Mismatch GCMs Tools for Atmosphere/ Ocean Modeling Hydrological Model Tools for Surface Earth Modeling GCMs accuracy decreases from free tropospheric variables to surface variables, while the variables at the ground surface have direct use in water balance computations. Working Variables Mismatch GCMs accuracy decreases from climate related variables, i.e. wind , temperature, humidity and air pressure to precipitation evapotranspiration , runoff and soil moisture, while the later variables are of key importance in hydrologic regimes. Impact of climate change Declining return period by increasing rainfall Return period of flood is declining by increasing rainfall in the future. As a result, future flood safety level is estimated to decrease. 【Image of declining return period at a certain area】 Maximum daily rainfall × 1.2 Return period (year) future current 100 current data projected data 50 Rainfall probability sheets Source: Okada, 2008 r Rainfall amount Impact of climate change Changing river discharge Decreasing run-offs during the peak demand season Deviation from traditional water use patterns will be required State of river run-offs after global warming (estimated) Earlier spring flooding Decreasing river run-offs Future River run-off Wasteful discharges Jan Source: Okada, 2008 Even if the rice paddy preparation season is advanced, available river run-offs in the demand season are insufficient. Apr Full Water in storage Present July Rice paddy preparation Oct Empty dams Unable to store Future Present Impact of climate change Impact of climate change on water quality Use of fossil fuel, etc. Global warming Water temperature rise (remaining warm) Temperature rise Increase of E. coli Increase of pests Fixed thermocline position Shifts in precipitation patterns Decrease of winter ice cover (increasing light transmission) From urban areas ← increased diffusion of nitrogen/phosphorus↓ Decreasing circulation in lakes Landslide in rain storm Soil erosion Bottom sedimentation of remains Increased turbidity Decrease of bottom-layer DO Leaking iron/ manganese Water safety Decrease of river DO Leaking hazardous substances Turbidity Smell/ taste Color Flux of hazardous substances Water safety Source: Okada, 2008 Savory water Products of treatment Increasing pesticide leaks with their increased use Flux into forests/soil (nitrogen saturation) NO3-N leaking into rivers upstream Phytoplankton proliferation Risk of infectious diseases Changing nitrogen cycle in the atmosphere Identification of the Climate Change in Java Island Rainfall Data Yearly Seasonal DRY Monsoon Storm WET DAILY MAX DJF TEST FOR THE TREND 1916-1980 1981-2000 MAM JJA TEST FOR THE CHANGES OF THE DISTRIBUTION 1916-1940 1941-1970 1971-2000 SON TEST FOR THE TREND MAP (result of the test) Source: RCWR-MPW TREND OF MAXIMUM DAILY RAINFALL IN JAVA ISLAND Catatan: • Data • Metode :Seri data hujan harian maksimum tahunan dari 1600 buah pos hujan (1916 2004) yang sudah lolos uji :Non Parametrik Tau Kendall dengan tingkat kepercayaan 95 % Analysis of Future Precipitation affected by Climate Change on Citarum River Basin, Indonesia ADB Intern Yutaka Araki Analysis on Citarum, Indonesia ・Most strategic river basin ・Climate Change could lead to more severe and frequent flooding, and raise sea level in the river mouth -12,000km^2 basin area -3 hydroelectric dams -1400MW -400,000ha Irrigation -80% of Jakarta’s water Analysis on Citarum, Indonesia Target period ・50 & 80 years later (2046-2065, 2081-2100 (+1981-2000)) ・based on 2 CO2-emission-scenario - SRES A1B & B1 Tools ・17(/25 )GCMs in CMIP3 SRES (Special Report on Emissions Scenarios) A1「High economic growth」 Globalization A1FI:enphasis on fossil fuel A1B: Balanced energy use A1T: Non fossil fuel.(Technical innovation in Energy) A1 B1 A2「Differentiated world」 slower technological change, less emphasis on economic, social, and cultural interactions between EnvironmentEconomyregions, Economic growth is uneven oriented oriented B1「Sustainable development」 pay increased attention to the environmental, Technological change plays an important role A2 B2 B2「Local self-reliance and stronger communities」 shift toward local and regional decision-making structures and institutions, Regionalization Originating Group(s) Country CMIP3 I.D. 20c3m SRES A1B Beijing Climate Center China BCC-CM1 - - Bjerknes Centre for Climate Research Norway BCCR-BCM2.0 - - National Center for Atmospheric Research USA CCSM3 1980-1998 2046-2064,2080-2098 Canadian Centre for Climate Modelling & Analysis Canada CGCM3.1(T47) 1981-1999 2046-2064,2081-2099 Canadian Centre for Climate Modelling & Analysis Canada CGCM3.1(T63) 1981-1999 2046-2064,2081-2099 Météo-France / Centre National de Recherches Météorologiques France CNRM-CM3 1981-2000 2046-2065,2081-2100 CSIRO Atmospheric Research Australia CSIRO-Mk3.0 1981-1999 2046-2064,2081-2099 CSIRO Atmospheric Research Australia CSIRO-Mk3.5 1981-1999 2046-2064,2081-2099 Max Planck Institute for Meteorology Germany ECHAM5/MPI-OM 1981-2000 2046-2065,2081-2100 Meteorological Institute of the University of Bonn, Meteorological Research Institute of KMA, and Model and Data group. Germany / Korea ECHO-G 1979-1997 2044-2062,2078-2096 LASG / Institute of Atmospheric Physics China FGOALS-g1.0 - - US Dept. of Commerce / NOAA / Geophysical Fluid Dynamics Laboratory USA GFDL-CM2.0 1981-1999 2046-2064,2081-2099 US Dept. of Commerce / NOAA / Geophysical Fluid Dynamics Laboratory USA GFDL-CM2.1 1981-1999 2046-2064,2081-2099 NASA / Goddard Institute for Space Studies USA GISS-AOM 1981-2000 2046-2065,2081-2100 NASA / Goddard Institute for Space Studies USA GISS-EH - - NASA / Goddard Institute for Space Studies USA GISS-ER - - Instituto Nazionale di Geofisica e Vulcanologia Italy INGV-SXG - - Institute for Numerical Mathematics Russia INM-CM3.0 1981-2000 2046-2065,2081-2100 Institut Pierre Simon Laplace France IPSL-CM4 1981-1999 2046-2064,2081-2099 Center for Climate System Research (The University of Tokyo), National Institute for Environmental Studies, and Frontier Research Center for Global Change (JAMSTEC) Japan MIROC3.2(hires) 1981-2000 2046-2065,2081-2100 Center for Climate System Research (The University of Tokyo), National Institute for Environmental Studies, and Frontier Research Center for Global Change (JAMSTEC) Japan MIROC3.2(medres) 1981-2000 2046-2065,2081-2100 Meteorological Research Institute Japan MRI-CGCM2.3.2 1981-1999 2046-2064,2081-2099 National Center for Atmospheric Research USA PCM 1980-1998 2046-2064,2080-2098 Hadley Centre for Climate Prediction and Research / Met Office UK UKMO-HadCM3 - - Hadley Centre for Climate Prediction and Research / Met Office UK UKMO-HadGEM1 - - Target Area ←Citarum River Basin 1 2 3 4 CCSM3.0 (USA) 5 PCM (USA) Analysis items • • • • • Rainfall days over 50,10 mm/day No rainfall days / consecutive no rainfall days Annual rainfall Seasonal rainfall (dry and rainy) Probable daily rainfall (5,10,100 years return) - Flood/City drainage - Irrigation/Drought management - Water Management No rainfall days no rainfall days 1.2 1.15 1.1 1.05 12%UP A1B B1 1 0.95 0.9 1981-2000 2046-2065 number of model which shows increase A1B 80years later B1 70% (12/17) Likely 50years later 65% 70% 50years later 80years later (11/17) More likely than not 65% (12/17) Likely (11/17) More likely than not 2081-2100 Heavy rainfall days (>50mm/day) Heavy rainfall days (>50mm/day) 3.5 3 2.5 2 A1B 1.5 B1 1 0.5 0 1981-2000 2046-2065 number of model which shows increase A1B 50years later 80years later B1 90% (9/10) very likely 80% (8/10) likely 50years later 90% (9/10) very likely 80years later 80% (8/10) likely 2081-2100 Annual rainfall Annual rainfall 1.1 A1B 1 B1 0.9 1981-2000 A1B B1 A1B B1 2046-2065 number of model which shows increasing rainfall 50years later 53% (9/17) 80years later 59% (10/17) 50years later 53% (9/17) 80years later 65% (11/17) number of model which shows increasing fluctuation (root-mean-square deviation) 50years later 53% (9/17) 80years later 47% (8/17) 50years later 53% (9/17) 80years later 47% (8/17) 2081-2100 Seasonal rainfall Dry season Rainy season 1.1 1.08 1.06 1.04 1.02 1 0.98 0.96 0.94 1.1 1.08 1.06 1.04 1.02 1 0.98 0.96 0.94 1981-2000 2046-2065 2081-2100 number of model which shows decreasing trend (Dry season) A1B B1 50years later 53% (9/17) 80years later 65% (11/17) 50years later 59% (10/17) 80years later 41% (7/17) A1B B1 1981-2000 2046-2065 2081-2100 number of model which shows increasing trend (Rainy season) A1B B1 50years later 35% (6/17) 80years later 71% (12/17) 50years later 41% (7/17) 80years later 82% (14/17) Longest consecutive no rainfall days Longest consecutive no rainfall days 1.4 1.2 1 0.8 A1B 0.6 B1 0.4 0.2 0 1981-2000 2046-2065 number of model which shows increase A1B B1 50years later 65% (11/17) ) More likely than not 80years later 65% (11/17) ) More likely than not 50years later 60% (10/17) ) More likely than not 80years later 60% (10/17) ) More likely than not 2081-2100 Probable rainfall nonexceedance probability 99.9999 ECHAM5/MPI-OM, Log-normal Probability Paper (Cunnane) 99.999 99.99 99.9 99 ■20C3M 1981-2000 ▲A1b 2046-2065 ◆A1b 2081-2100 ■B1 2046-2065 ●B1 2081-2100 90 70 50 30 R² = 0.958 R² = 0.9775 R² = 0.9685 R² = 0.8955 R² = 0.9564 10 1 0.1 0.01 0.001 0.0001 10 100 mm/day A1B Number of models which show more severe distribution than now 5-year probable rainfall 10-year probable rainfall 100-year probable rainfall B1 2046-2065 2081-2100 2046-2065 2081-2100 82% 94% 76% 14(/17) 16(/17) 13(/17) 53% 9(/17) 1.18 1.31 1.35 1.36 1.14 1.15 1.17 1.18 1.2 1.18 1.20 1.20 Incremental Ratio of Daily Probable Rainfall (10year), A1B,50years later, from 17 models IPSL-CM4 MIROC3.2(hires) GFDL-CM2.0 CGCM3.1(T63) CCSM3 MIROC3.2(medres) GFDL-CM2.1 CSIRO-Mk3.0 ECHAM5/MPI-OM ECHO-G GISS-AOM MRI-CGCM2.3.2 CNRM-CM3 PCM INM-CM3.0 CSIRO-Mk3.5 CGCM3.1(T47) Average=1.2 (from 17 models) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 Flood Simulation ・Area Citarum Upper Basin ・Return period 10 years ・Climate Current and 50 years later(A1B) Nanjung Nanjung Dayeuh Dayeuh Kolot Kolot Majalaya Majalaya Design Rainfall Current Design Rainfall 1 Design Hydrograph Future Design Rainfall under Climate Change Discharge (m^3/s) 1.2 Hydrological Model Climate Change Current Climate T Citarum Upper Basin cibeureum 45 40 35 30 25 20 15 10 5 0 Citepus Cipamakolan 16 50 14 12 10 40 8 0 20 40 60 80 100 120 Cikapundung 6 2 50 years later(A1B) 30 100 4 Current 20 80 0 0 20 40 Current 60 80 100 120 60 10 Cikeruh 40 50 years later(A1B) 0 20 250 0 0 0 20 40 60 Current 80 100 20 40 120 60 Current 80 100 120 200 150 50 years later(A1B) 100 50 years later(A1B) 50 0 0 20 40 60 Current 80 100 120 50 years later(A1B) Cidurian 30 25 20 15 10 5 0 0 20 40 Current 60 200 Ciwidey 120 Cisangkuy Citarik 200 150 50 Increase! 120 100 80 150 40 100 100 140 60 80 50 years later(A1B) 20 0 0 20 40 Current 60 80 100 120 50 years later(A1B) Cicadas 0 0 20 40 60 80 100 Cisangkuy 120 14 12 200 Current 50 years later(A1B) 10 100 150 8 6 100 4 2 50 0 0 0 0 20 40 Current 60 80 50 years later(A1B) 100 120 20 50 40 Current 60 80 100 120 50 years later(A1B) Cirasea 80 70 60 50 40 30 0 20 10 0 0 20 40 Current 0 60 20 40 Current 60 80 80 100 120 100 50 years later(A1B) 50 years later(A1B) 120 majalaya-Citarum Main 200 150 100 50 0 0 20 40 Current 60 80 50 years later(A1B) 100 120 Flood Simulation Orange – Current Design Flood Purple – Future Design Flood ADB Delft Hydraulics Institutional Strengthening For Integrated Water Resources Management in the 6 CIS River Basin Territory (Package C) Upper Citarum Basin Flood Management Project UCBFM Flood Management Strategy ‘No regret’ – urgent program February 25, 2011 JanJaap Brinkman, Deltares Understanding the basics Is there any change? • Land-use change? – Yes, urbanization • Climate change increasing floods? – No, not yet • Topography change? – Yes, subsidence • River change? – Yes, maintenance and ‘controlled’ river normalization • Flood management change? – Yes, urgently required – ‘space for water management’ Climate change? Climate Change -Trend analysis of daily point and basin rainfall extremes Annual maximum point and basin daily rainfall extremes in Bandung basin 140 basin rainfall by all stations basin rainfall by BMKG-stations average point extremes by BMKG Linear trend-all stations Extreme daily rainfall (mm) 120 100 80 60 40 20 0 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 Climate Change - Trend analysis annual rainfall in Bandung basin, Period 1879-2007 Estimate of annual rainfall in Bandung basin, Period 1879-2007 3500 3000 Annual rainfall (mm) 2500 2000 1500 Annual basin rainfall Period average 1000 500 0 1860 1880 1900 1920 1940 1960 1980 2000 2020 Climate Change - Seasonal rainfall in Citarum u/s Nanjung, Period 1879-2010 Seasonal rainfall (Jan-Mar) in Citarum basin, Period 1979-2010 1400 Jan- Mar 2010 1285 mm 1200 Rainfall (mm) 1000 800 600 400 200 0 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 Rainfall characteristics Lessons learnt from the 2009-2010 flood season. Bandung basin – hydrology • Historic floods not related to basin wide rainfall – Floods relate to local rainfall 5-Day rainfall extremes in basin u/s of Dayeuh Kolot with occurrence of 5-day rain-flood damages 250 5 day rainfall causing flood damage 225 200 175 Rainfall (mm) average 150 125 100 75 50 25 0 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 SUMMARY Advanced GCM, RCM, and the hydrological model and also methodologies for comprehensive modeling have been developed. The two modeling systems have recently been used for quantification of the hydrological impacts of future climate change. However, the research on hydrological change is still in its infancy both with respect to model accuracy and uncertainty. Traditionally, based on the output of global or regional climate models, hydrological models have been run as stand alone models. This means that the feedbacks to the atmosphere are neglected which has an unknown impact on the predictions of the climate change, particularly at the local scale. New model should be developed by combining the regional climate model and the hydrological model. As part of the integrated model a statistical downscaling and biascorrection method should be developed for conversion of data from large climate grids to small hydrological grids. New methodologies and tools should be developed to enable easier and more accurate use of regional scale climate and hydrological models to address local scale water resources problems. Thank you for your kind attention ! KARIKATUR: KOMPAS/ Sabtu 10 Februari 2007