Mapping Multiple Climate-related Hazards in South Asia

Mapping Multiple Climate-related Hazards in South Asia

Amarnath, G.; Alahacoon, N.; Smakhtin, V.; Aggarwal, P. 2017. Mapping multiple climate-related hazards in South Asia. Colombo, Sri Lanka: International Water Management Institute (IWMI). 41p. (IWMI ResearchReport 170). doi: 10.5337/2017.207

All countries experience multiple climate-related risks that vary spatially and in time, and the combined impact of such risks may turn out to be very severe. To prioritize climate adaptation strategies, there is a need for quantitative, regional-level assessment of these risks. This report suggests methods for mapping such risks and estimating their impacts on people and agriculture in South Asia. Regional, country-wise and sub-national assessment of five climaterelated risks – floods, droughts, extreme rainfall, extreme temperature and sea-level rise – is carried out. The approach involves overlaying climate hazard, sensitivity and adaptive capacity maps, and follows the vulnerability assessment framework of the Intergovernmental Panel on Climate Change (IPCC). A combined index based on hazard, exposure and adaptive capacity is introduced to identify areas susceptible to extreme risk.

The study presents a detailed and coherent approach to fine-scale climate hazard mapping that allows unambiguous identification of regions in South Asia which are most vulnerable to climate-related hazards. The study used data on the spatial distribution of various climaterelated hazards in 1,398 sub-national areas of Bangladesh, Bhutan, India, Nepal, Pakistan and Sri Lanka. An analysis of country-level population exposure showed that approximately 750 million people are affected by combined climate hazards. Of the affected population, 72% is in India, followed by 12% each in Bangladesh and Pakistan. The remaining 4% is divided across Bhutan, Nepal and Sri Lanka. It was identified that agriculture was the most vulnerable sector due to its exposure to climate extremes, and that climatic upheavals had a direct impact on the economy of the country. An analysis of individual climaterelated hazards indicates that floods and droughts affect agricultural areas the most, followed by extreme rainfall, extreme temperature and sealevel rise. Based on this vulnerability assessment, the regions that are most vulnerable to climaterelated hazards in South Asia were identified – all the regions of Bangladesh; the Indian states of Andhra Pradesh, Bihar, Maharashtra, Karnataka and Orissa; Ampara, Puttalam, Trincomalee,Mannar and Batticaloa in Sri Lanka; Sindh and Balochistan in Pakistan; Central and East Nepal; and the transboundary river basins of Indus, Ganges and Brahmaputra.