The Asian Monsoon, which brings rains that sustain billions of people in India, China, Pakistan, Thailand and other countries, is seeing a weakening trend that's unprecedented in at least the past 448 years, according to a new study based in part on tree ring records. The culprit, the study finds, is aerosol pollution from coal-fired power plants along with other sources.
Why it matters: The Asian Monsoon, comprised of several regional climate cycles, is the natural irrigation system for much of Asia, from southern India to northwest China. It's one of the most important climate cycles in the world, driven by the contrast in temperatures between the land and sea. If, as the new study shows, air pollution from coal-fired power plants and other sources is weakening the monsoon, it could imperil food security in a rapidly growing part of the world.