Regional Climate Change Scenarios for India and Implications for Water Availability Issues K. Krishna Kumar CIRES Visiting Fellow, University of Colorado, Boulder K. Rupa Kumar, N.R. Deshpande, V. Prasanna and S.K. Patwardhan Indian Institute of Tropical Meteorology, Pune, India

Indian Summer Monsoon Flow

Mean Rainfall Patterns Data Source: CMAP ( ) Summer Monsoon (mm/season) Annual (mm/year)

Mean Annual Cycle of All-India Mean Monthly Rainfall

All-India Summer Monsoon Rainfall ( ) (Based on IITM Homogeneous Monthly Rainfall Data Set)

Agriculture Facts  India lives mainly in its villages, 600,000 of them  Roughly 65% of the population is rural  India’s growth in per capita food production during was about 1.6% per annum – the highest in the world during this period  Agriculture provides livelihood to about 65% of the labor force  Agriculture contributes nearly 29% to the GDP  In terms of fertilizer consumption, India ranks 4 th in the world  About 43% of India’s geographical area is used for agriculture

IRRIGATIONCrop Area under crop (mn. hec) Irrigated area under crop (mn. hec.) Irrigated area as % of total area under crops Foodgrains Rice Wheat Non- foodgrains Groundnut9220 Cotton7333 Sugarcane4386 Total

Total Foodgrain Production in India and its Relation to Indian Rainfall

India’s Water Situation

Proposed River Linkages

Development of Climate Change Scenarios of Rainfall and Temperature over the Indian region Potential Impacts: Water Resources Water Resources Agriculture Agriculture Sea Level Rise Sea Level Rise and many more sectors…

Development of Future Scenarios of Rainfall & Temperature over India IS92a (8 Coupled Atmos.-Ocean GCMs) IS92a (8 Coupled Atmos.-Ocean GCMs) SRES A2 (5 AOGCMs) SRES A2 (5 AOGCMs) SRES B2 (5 AOGCMs) SRES B2 (5 AOGCMs) Simulations are generally available for about 200 years (~1870s till 2100)

A1: A world of rapid economic growth and rapid introductions of new and more efficient technologies A2: A very heterogeneous world with an emphasis on family values and local traditions B1: A world of ‘dematerialization’ and introduction of clean technologies B2: A world with an emphasis on local solutions to economic and environmental sustainability IPCC 2001 climate change scenarios 5 state-of-the-art climate models run until 2100 with various emission scenarios

AOGCM simulations used from IPCC-DDC Using greenhouse gas forced (following IS92A, SRES (A2/B2) scenarios) simulations of 8 different coupled ocean-atmosphere general circulation models, the rainfall and temperature scenarios for ; ; ; compared to the baseline period of are generated for the Indian region. The models used are: 1.Canadian Center for Climate modeling (CCC) model. 2.Center for Climate Research studies (CCSR) model. 3.Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO) model. 4.Deutsches Klima Rechen Zentrum (DKRZ) model. 5.Geophysical Fluid Dynamics Laboratory (GFDL) model. 6.Hadley Centered model.(HadCM3) 7.Max-planck Institute(MPI) model. 8.National Center for Atmospheric Research (NCAR) model.

Indian Summer Monsoon Patterns as simulated by 8 coupled AOGCMs Indian Summer Monsoon Patterns as simulated by 8 coupled AOGCMs

Annual Cycles of All-India mean rainfall in the control simulations of coupled AOGCMs

Annual Surface Air Temperature Patterns over India simulated by 8 coupled AOGCMs

AOGCM Scenarios of all- India summer monsoon rainfall and mean annual surface temperature

AOGCM Projected change in summer monsoon rainfall, relative to

AOGCM Projected change in mean annual surface air temperature, relative to

Future Change in Monsoon Rainfall Variability (IS92a)

High-resolution Climate Change Scenarios using Regional Climate Model ( ＨａｄＲＭ２／ HadRM3)

GCMs to Regional Adaptive Responses : Modelling Path

The Hadley Centre Regional Climate Models (HadRM2/HadRM3H/PRECIS) ¥ High-resolution limited area model driven at its lateral and sea- surface boundaries by output from HadCM ¥ Formulation identical to HadAM ¥ Grid : 0.44° x 0.44° ¥ One-way nesting ¥ Climate change simulations performed by the Hadley Centre using HadRM2 for the Indian region ¥ HadRM3H as well as PRECIS installed at IITM; Climate change simulations and scenario development at an advanced stage by using PRECIS at IITM

Model Orography GCMRCM

HadRM2 scenarios ¥ Two experiments : Control (1990 GHG Forcing) and IS92a scenario ( ) ¥ Each experiment has 20 years data ¥ Monthly and Daily data on various parameters ¥ Regridded data with uniform horizontal grid spacing ¥ Spatial means for administrative units (states)

Indian Summer Monsoon Simulations by HadRM2

All-India Mean Monthly Rainfall

State-wise mean monsoon precipitation change scenarios : HadRM2

Indian Annual Surface Temperature Simulations by HadRM2

State-wise Mean Annual Temperature Change Scenarios : HadRM2

Simulation of Monsoon Depressions/Cyclonic Storms in HadRM2 and Likely Future Changes Changes in Monsoon Depression/Cyclonic Storm Tracks in GHG Scenarios. Changes in Monsoon Depression/Cyclonic Storm Tracks in GHG Scenarios. Frequency of Depressions/Cyclones. Frequency of Depressions/Cyclones. Intensity of Storms. Intensity of Storms.

Criteria adopted for the identification of cyclonic storms (this includes severe storms and monsoon depressions) At least 2 days Duration > 15 m/s Max. Wind Speed < -5hPa SLP Departure Local Minimum Sea level Pressure (SLP)

A typical Monsoon Depression as simulated in the regional model

Monsoon Depression Tracks as simulated in HadRM2 control and GHG Experiments

Pre and Post- Monsoon Cyclonic Storms and likely Changes in GHG Runs

Frequency of monthly cyclonic disturbances (Max intensity in m/s) as simulated by HadRM2 for

NATCOM Workshop, IIM Ahmedabad, Likely Changes in Extreme Rainfall and TMAX/TMIN Temperatures in India

HadRM2 Projections ( ) of Rainfall Intensity Change in Annual number of rainy days Change in rainfall per rainy day

Impact of Climate Change on the daily Extreme Rainfall (cm) amounts in India

Location of Stations Considered in Extreme Temperature Analysis

HadRM2 Projections ( ) of Temperature Extremes Change in extreme Maximum Temperature Change in extreme Minimum Temperature

River Basins under Study

Change in Monthly Rainfall in GHG Scenarios