After a spring of deadly heat waves, summer floods have killed more than 1,100 people in Pakistan. Since June, rains have washed away buildings, submerged homes and destroyed roads. One-third of the country is underwater. From a report: Scientists can’t yet say exactly how climate change has shaped the disaster, but they know that global warming is sharply increasing the likelihood of extreme rain in South Asia, home to a quarter of humanity. There is little doubt that it made this year’s monsoon season more destructive. Today, I’ll talk about some of the climate factors in play and why Pakistan, a country that has done very little to cause global warming but is now among the most vulnerable to its effects, has been hit so hard. The South Asian summer monsoon is part of a regional weather pattern. Basically, winds tend to blow from the southwest from June through September. That onshore breeze brings wet weather. In normal times, that’s generally a good thing. Farmers all over the region count on monsoon rains for their crops.
But these are no longer normal times. Global warming means that water evaporates much faster out at sea. And, a warmer atmosphere can hold more moisture. So, monsoons risk bringing way too much rain. Researchers will need time to conduct attribution studies to understand exactly what happened this summer, but Steven Clemens, a professor of earth, environmental and planetary sciences at Brown University, said the months of deluge in Pakistan are “super consistent with what we expect in the future” as the planet heats up. This monsoon season, rainfall in Pakistan has been nearly three times the national average of the past 30 years, the country’s disaster agency said. In Sindh Province, which borders the Arabian Sea to the south, rainfall is nearly five times the average.