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Climate change likely helped cause deadly Pakistan floods, scientists find

Published September 19, 2022 at 1:18 PM EDT

People from flood-affected areas wait to get free food distributed by a charity, in Chachro, near Tharparkar, a district of southern Sindh province, Pakistan, Monday, Sept. 19, 2022. Pakistan said Monday there have been no fatalities for the past three days from the deadly floods that engulfed the country since mid-June, a hopeful sign that the nation is turning a corner on the disaster. (AP Photo/Pervez Masih)

It is likely that climate change helped drive deadly floods in Pakistan, according to a new scientific analysis. The floods killed nearly 1500 people and displaced more than 30 million, after record-breaking rain in August.

The analysis confirms what Pakistan's government has been saying for weeks: that the disaster was clearly driven by global warming. Pakistan experienced its wettest August since the country began keeping detailed national weather records in 1961. The provinces that were hardest hit by floods received up to eight times more rain than usual, according to the Pakistan Meteorological Department.

Climate change made such heavy rainfall more likely, according to the analysis by a group of international climate scientists in Pakistan, Europe and the United States. While Pakistan has sometimes experienced heavy monsoon rains, about 75 percent more water is now falling during weeks when monsoon rains are heaviest, the scientists estimate.

The analysis is a so-called attribution study, a type of research that is conducted very quickly compared to other climate studies, and is meant to offer policymakers and disaster survivors a rough estimate of how global warming affected a specific weather event. More in-depth research is underway to understand the many ways that climate change affects monsoon rainfall.

For example, while it's clear that intense rain will keep increasing as the Earth heats up, climate models also suggest that overall monsoon rains will be less reliable. That would cause cycles of both drought and flooding in Pakistan and neighboring countries in the future.

Such climate whiplash has already damaged crops and killed people across southeast Asia in recent years, and led to a water crisis in Chennai, Indiain 2019.

The new analysis also makes clear that human caused climate change was not the only driver of Pakistan's deadly floods. Scientists point out that millions of people live in flood-prone areas with outdated drainage in provinces where the flooding was most severe. Upgrading drainage, moving homes and reinforcing bridges and roads would all help prevent such catastrophic damage in the future.