By the turn of this century, rising temperatures caused as a result of global warming may delay and even weaken the South Asian summer monsoon. So predicts a new climate modeling study which has indicated that this effect may adversely affect agriculture in India, Pakistan, Bangladesh and Nepal.
The study, by a Purdue University research group, found that climate change could influence monsoon dynamics and cause less summer precipitation, a delay in the start of monsoon season and longer breaks between the rainy periods.
According to Noah Diffenbaugh, whose research group led the study, the summer monsoon affects water resources, agriculture, economics, ecosystems and human health throughout South Asia.
"Almost half of the world's population lives in areas affected by these monsoons, and even slight deviations from the normal monsoon pattern can have great impact," said Diffenbaugh.
"Agricultural production, water availability and hydroelectric power generation could be substantially affected by delayed monsoon onset and reduced surface runoff," he added.
Alternatively, the model projects increases in precipitation over some areas, including Bangladesh, which could exacerbate seasonal flood risks.
The summer monsoons are responsible for approximately 75 percent of the total annual rainfall in major parts of the region and produce almost 90 percent of India's water supply.