Work package 1
WP 1: Climate change impacts on water availability (lead: TERI)
The first WP aims to depict water availability today and in the future. This WP will capture the physical dimensions of changes in the climate as well as water resources using modelling and statistical analysis. It will generate scenarios of exposure to extreme events over a high spatial resolution of 25*25 km and for specific future time slices e.g. 2030s, 2050s, 2070s and 2100. Results from WP 1 will feed into WP 2 and 3 to link changes in physical parameters to impacts on the natural and human systems. WP 1 encompasses the following activities:
Activity 1.1: Assemblage of data on past climate and water availability in Maharashtra: For predicting future climate conditions it is necessary to establish a good database on historic conditions. We will therefore collect historical observational data e.g. from the Indian Meteorological Department and the Hydrological Information System (HIS) and conduct a literature review of past trends in climate extremes in Maharashtra. Moreover we will identify flood and drought prone areas, to improve the selection of water testing sites (activity 2.2).
Activity 1.2: Construct a baseline for average water availability and extreme events using observational climate records: For climate projections, a regional climate model called PRECIS (Providing Regional Climate for Impact Studies) is used. PRECIS is an atmospheric and land surface model of limited area and high resolution which is locatable over any part of the globe. Th horizontal resultion is either 50 or 25 km, depending on the data base.
Activity 1.3: Validation of model baseline using the historical observational data: The constructed baseline for PRECIS model will be validated using observational data from Indian Meteorological Department, records or through other available sources. The data for validation will be independent from the data used for the construction of the baseline.
Activity 1.4: Develop projections for average water availability and extreme events (“future normal” and “future extreme” conditions): Applying PRECIS, projections for average water availability and of extremes under a moderate and extreme climate future will be developed for specific time-slices (for example 2030s, 2050s, 2070s and 2100s) at 25km by 25km spatial resolution using relevant IPCC scenarios.
Activity 1.5: Assessment of future climate impacts on surface water availability: Surface water availability will be assessed using simplified hydrological model approaches based on Hydrologic Response Units as e.g. the Soil and Water Assessment Tool (SWAT). Climate projections come from activity 1.4, socio-economic trends from activity 3.1. The results will help us to evaluate the effects of climate change on streamflow regimes and groundwater recharge rate and identify drought prone areas.