Approach and Methodology
There are three critical gaps in the efforts to develop a climate simulation platform for India: the first is the lack of a careful calibration with focus on the Indian monsoon region; the second is the absence validated climate simulation at resolutions sufficiently high to make them applicable to regional impact analysis. The third is the absence of associated process models to translate the climate change scenarios to policy decisions. The present project is aimed at filling these critical gaps to develop a platform for regional climate modeling and impact analysis.
While the dynamical models are quite generic at one level, they exhibit significant variations in their performance with geographical locations and processes due to poor understanding and non-unique representation of various physical processes. Calibration and optimization of model configuration can significantly improve model performance, as shown below. It is thus necessary to use a model primarily calibrated for the monsoon region.
Secondly, while there now exist climate simulations from a large number of models, they show large inter-model dispersions. Further, the simulations from these models are often at resolution too coarse to capture strong spatial inhomogenieties over the monsoon region. It is necessary that impact and sustainability analyses are carried out at resolution meaningful for impact and sustainability analysis.
A basic climate model, however, need to be interfaced with various processes, agricultural, industrial, engineering and others, to translate the inputs from the climate model to quantitative assessments of sustainability and design of mitigation strategies. This component, equally critical for assessing mitigation and sustainability, has very wide scope; it is here that the diverse expertise at CSIR laboratories can be integrated effectively. In this fist phase of the project this component will be limited to development and integration of models on crop (CIMAP), vector borne disease (IICT) and material (NAL). Models of these processes will be developed by –MMACS in collaboration with the participant laboratories and interfaced with the basic climate model to generate multipl-scenario assessments.
Validation and calibration of climate and sustainability models require specific observed inputs on various environmental parameters like water withdrawal, emission, landuse and others. While archived data will be used wherever possible, additional critical data will be generated through targeted observations. The identification of parameters to be observed, frequency and locations of observation etc will be determined through Project Implementation Meetings.
The evolution of the future climate is likely to be very different from that in the past owing to significant anthropogenic forcing, from land use to energy products, in the present and future eras. The local (or regional) climate change scenarios will be therefore integrated to processes like energy use and land use to develop effective adaptation and mitigation strategies. The increasing intensity of tropical cyclones may necessitate redesign of codes with respect to wind load. Emission of black carbon beyond a limit may cool the surface to reverse the land-equator thermal gradient and diminish the monsoon, even in the presence of natural global warming. At the same time, adaptation of cleaner energy may have a positive effect. These aspects will be studied through multiple-scenario simulations for quantitative estimations.
The simulation and projection of the regional climate in the overall global environment will be carried out using internationally accepted climate models after calibrating and validating for the Indian region. Models of sustainability will be interfaced to these climate models for quantitative multiple-scenario assessment and projections of sustainability under different conditions. Finally impact and effectiveness of mitigation strategies will be examined through long-period sensitivity experiments.
The central component of the methodology will be to use state-of-the-art climate models to generate and validate (for present times) simulation of regional climate over India. The validated model will then be used to generate quantitative climate change projections over the Indian region. The climate projections (such as maximum and minimum temperatures, rainfall and intensity) will be used as inputs for process models like crop growth, structural vulnerability and pest population to be used in sustainability and mitigation models.