Selection of Suitable General Circulation Model Outputs of Precipitation for a Humid Tropical Basin

Abstract

Climate change has an observed effect on the environment and ecosystem. Climate change study aids in visualisation of changes in the environmental processes as well as development of planning and adopting the strategies. General circulation models (GCMs) are widely used in understanding present and projecting future climate change. The uncertainties associated with the climate projections is a major risk in impact assessment studies and could be reduced with considering GCMs suitable for the region. The study attempts to select a suitable subset of GCMs for precipitation simulation in the humid tropical basin, Achencoil, Kerala, India. Three statistical indicators, correlation coefficient (CC), normalised root mean square deviation (NRMSD) and absolute normalised mean bias deviation (ANMBD), are considered to evaluate the GCMs with the historical observations. The entropy technique is assigned to determine the weight of each performance indicator. Multi-criterion decision-making approaches, compromise programming (CP) and preference ranking organisation method of enrichment evaluation (PROMETHEE-2) are applied individually to rank the GCMs. The ranking is then integrated with group decision-making approach. The GCMs, MIROC-ESM-CHEM, MIROC-ESM, BCC-CSM1-1 and NorESM1-M occupied the first four positions in replicating the historical rainfall in the basin. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.