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…

Interlinking of Rivers in India

Proposed River Linkages

Climate Scenarios: What are they ? A climate scenario is a plausible representation of future climate that has been constructed for explicit use in investigating the potential impacts of anthropogenic climate change.

Uncertainties in Climate Scenarios Specifying alternative emissions futures Specifying alternative emissions futures Uncertainties in converting emissions to concentrations Uncertainties in converting emissions to concentrations Uncertainties in converting concentrations to radiative forcing Uncertainties in converting concentrations to radiative forcing Uncertainties in modelling the climate response to a given radiative forcing Uncertainties in modelling the climate response to a given radiative forcing Uncertainties in converting model response into inputs for impact studies Uncertainties in converting model response into inputs for impact studies

Climate System

Climate Models Simplified mathematical representation of the Earth ’ s climate system Skill depends on the level of our understanding of the physical, geophysical, chemical and biological processes that govern the climate system Substantial improvements over the last two decades Sub-models : atmosphere, ocean, land surface, cryosphere, biosphere Typical Resolution of global models (atmosphere) : Horizontal km; Vertical ~ 1 km Small-scale processes : Parameterisation Coupled models (e.g., atmosphere-ocean) Sensitivity studies/Future projections Internal variability/Ensemble runs

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

Predicted precipitation change Source: IPCC 2001 Cubasch

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.

Global Summer (JJAS) Precipitation Patterns simulated by 8 coupled AOGCMs

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

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

Climate Change Scenarios of Rainfall over the Indian Region in 8 Coupled Models

Climate Change Scenarios of Surface Temperature over the Indian Region in 8 Coupled Models

Monsoon Precipitation Change (% of as compared to period) due to GHG Increase

Monsoon Precipitation Change (% of as compared to period) due to GHG Increase

Annual Surface Temperature Change (Deg. C in compared to period) due to GHG Increase

Future Change in Monsoon Rainfall Variability (IS92a)

Future Change in Monsoon Rainfall Variability (SRES/A2)

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

The Hadley Centre Regional Climate Models (HadRM2/HadRM3) High-resolution limited area model driven at its lateral and sea- surface boundaries by output from HadCM High-resolution limited area model driven at its lateral and sea- surface boundaries by output from HadCM Formulation identical to HadAM Formulation identical to HadAM Grid : 0.44° x 0.44° Grid : 0.44° x 0.44° One-way nesting One-way nesting Joint Indo-UK Collaborative research programme on climate change impacts in India Joint Indo-UK Collaborative research programme on climate change impacts in India Climate change simulations performed by the Hadley Centre using HadRM2 for the Indian region (the output is being currently analysed by IITM) Climate change simulations performed by the Hadley Centre using HadRM2 for the Indian region (the output is being currently analysed by IITM) HadRM3 installed at IITM; Climate change simulations and scenario development in progress at IITM HadRM3 installed at IITM; Climate change simulations and scenario development in progress at IITM

Model Orographies in GCM and RCM

Observed and Simulated Indian Summer Monsoon Rainfall (GCM vs. RCM)

Observed and Simulated (GCM and RCM) Surface Air Temperature over India

Indian Summer Monsoon Simulations by HadRM2

Indian Annual Surface Temperature Simulations by 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

Location of Stations Considered in Extreme Temperature Analysis

Simulation of No. of Rainy Days in the Hadley Center Regional Model and likely future changes in

Intensity (mm/day) of Rainfall per rainy day and likely future changes in

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

Impact of Climate Change on the daily Extreme Tmax. (Deg. C) India

Impact of Climate Change on the daily Extreme Tmin. (Deg. C) India