Highlights
Excerpts from the NYT report: Devastating flooding that has swamped one-fifth of Pakistan and left millions homeless is likely the worst natural disaster to date attributable to climate change, U.N. officials and climatologists are now openly saying.
Most experts are still cautioning against tying any specific event directly to emissions of greenhouse gases. But scientists at the World Meteorological Organization (WMO) in Geneva say there’s no doubt that higher Atlantic Ocean temperatures contributed to the disaster begun late last month.
Atmospheric anomalies that led to the floods are also directly related to the same weather phenomena that a caused the record heat wave in Russia and flooding and mudslides in western China, said Ghassem Asrar, director of the World Climate Research Programme and WMO. And if the forecasts by the Intergovernmental Panel on Climate Change (IPCC) are correct, then Pakistan’s misery is just a sign of more to come, said Asrar.
“There’s no doubt that clearly the climate change is contributing, a major contributing factor,” Asrar said in an interview. “We cannot definitely use one case to kind of establish precedents, but there are a few facts that point towards climate change as having to do with this.”
The flooding started slowly at the end of July and gradually accelerated over the past two weeks. Disaster assessment maps show that almost the entire northern part of Pakistan and most of its central region have been hit.
During the most intense storms, about a foot of rain fell over a 36-hour period. Parts of the affected areas, in particular Khyber-Pakhtunkhwa province (formerly Northwest Frontier province) received 180 percent of the precipitation expected in a normal monsoon cycle. More rain is expected in the days ahead.
Records show that the famed Indus River is at its highest water level ever recorded in the 110 years since regular record-keeping began. Estimates put the number of displaced people at somewhere between 15 million and 20 million, and the government believes about 1,600 are confirmed dead.
6.5 million need food, drinking water and medicine.
Zamir Akram, Pakistani ambassador to the U.N. center in Geneva, said floodwaters now cover an area roughly the size of England. Satellite surveys show about 160,000 square kilometers (62,000 square miles) is underwater, or about one-fifth of Pakistan’s landmass and roughly equivalent to the areas of Austria, Belgium and Switzerland combined.
Asrar at the WMO says higher-than-average Atlantic temperatures and conditions made ripe by the La Niña cycle of lower temperatures in the central Pacific Ocean created the perfect conditions for the rains. Experts acknowledge that the scale of this disaster has been made worse by a history of deforestation and land-use changes in the affected areas, but Asrar insists that the sheer volume of precipitation absorbed by clouds and then dumped on Pakistan is chiefly to blame.
The IPCC assessment reports note that higher ocean temperatures lead to more water vapor entering the atmosphere. This fact, Asrar said, already pointed toward a stronger than usual monsoon season in store for South Asia.
Abnormal airflow dumps supersaturated air
Normal air patterns would have dispersed this precipitation over as wide an area as possible. But an abnormal airflow caused by La Niña created a ridge of pressure that blocked the warm, saturated air from moving west to east normally, Arar said.
“Basically, this rift that was forming blocked the warm air moving from west to east, and then, on the other side, this air that was super saturated with water vapor had to precipitate all this excess water that was in the atmosphere, which created this unprecedented amount of rain in short period of time,” Asrar explained. “The connecting factor is that clearly the warming is a driver for all these events.”
Hundreds of thousands of homes have been completely swept away all over the country, and several communities have been cut off from the outside world as floodwaters washed bridges and roads away. Officials don’t yet know what the full cost of recovery will be, but all expect it to be tremendous — Akram in Geneva told reporters that the cost to rebuild Khyber-Pakhtunkhwa province, one of the hardest hit, would be at least $2.5 billion.
Photo credit: DFID – UK Department for International Development via Flickr