South Asian precipitation: a seamless assessment (SAPRISE)

Lead PIs

Prof Mat Collins, University of Exeter, UK

Prof Krishna AchutaRao, Indian Institute of Technology (IIT) Delhi, India

Indo-UK Partners

University of Reading, UK

Met Office Hadley Centre, UK

Indian Centre for Climate and Societal Impacts Research (ICCSIR), Gujarat, India

IITM, Pune, India

IIT Kanpur, India

IIT Kharagpur, India

National Centre for Medium Range Weather Forecasting (NCMRWF), India

IMD, India

Start and End Date

February 2012 - July 2015

Funders

UKRI-Natural Environment Research Council (NERC), UK

Ministry of Earth Science, GoI

Summary of Project

The Indian summer monsoon provides about 80% of annual rainfall to around a billion people in South Asia. Variations in its timing, intensity and duration have a dramatic impact on society. The weather and climate in the South Asian region is influenced by the weather and climate in the Indian and remote ocean basins via what are known as teleconnections (remote connections). It remains a considerable challenge to predict seasonal, decadal and longer-term changes in the South Asian monsoon.

SAPRISE brought together UK and Indian scientists to make progress in understanding what affects the South Asian monsoon on different time scales. The outcomes include:

• Significant differences were found to exist between different rainfall data sets and this hampers model evaluation

• Demonstrating the importance of sea-surface temperatures in the Arabian Sea and land-surface processes in simulating the monsoon rainfall. Increasing model spatial resolution is not a panacea; representation of physical processes in models must be improved.

• The research highlights an increasing frequency of extreme El Niño and La Niña under climate change, which will affect monsoon rainfall.

• SAPRISE has shown that aerosol particles have contributed to a reduction in rainfall in the latter part of the 20th century. As aerosol emissions decline in the future, an increasing rainfall signal is projected to emerge