Journal article

Irrigation-Induced Land-Atmosphere Feedbacks and Their Impacts on Indian Summer Monsoon

Chihchung Chou, Dongryeol Ryu, Min-Hui Lo, Hao-Wei Wey, Hector M Malano

JOURNAL OF CLIMATE | AMER METEOROLOGICAL SOC | Published : 2018

Abstract

From the 1980s, Indian summer monsoon rainfall (ISMR) shows a decreasing trend over north and northwest India, and there was a significant observed reduction in July over central and south India in 1982-2003. The key drivers of the changed ISMR, however, remain unclear. It was hypothesized that the large-scale irrigation development that started in the 1950s has resulted in land surface cooling, which slowed large-scale atmospheric circulation, exerting significant influences on ISMR. To test this hypothesis, a fully coupled model, the CESM v1.0.3, was used with a global irrigation dataset. In this study, spatially varying irrigation-induced feedback mechanisms are investigated in detail at ..

View full abstract

Grants

Awarded by Ministry of Science and Technology, Taiwan


Funding Acknowledgements

The authors thank the Climate and Global Dynamics Laboratory (CGD) at the National Center for Atmospheric Research (NCAR) for maintaining the CESM. We also thank the Indian Institute of Tropical Meteorology (IITM) for making rainfall observation records available and the Indian Meteorological Department (IMD) for producing and providing the gauged-based rainfall data (https://www.tropmet.res.in/).We thank the editor and anonymous reviewers for their valuable comments that helped us to improve the manuscript. The simulation results analyzed in this work are available upon request (chihchungc@student.unimelb.edu.au).This study was supported by the Melbourne International Research Scholarship (MIRS) and the Ministry of Science and Technology, Taiwan, Grant MOST 106-2111-M-002-010-MY4.