Once purely the realm of climate scientists and environmentalists, the study of global warming-induc

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The images of Pakistan's 2010 devastating flood still haunt. Women up to their necks in the waters of the swollen Indus River, carrying children to safety. Men wading through the brown currents with bags of rice on their heads and young ones on their backs.
The numbers, too, were staggering. Triggered by unusually heavy monsoon avc rains, the fast-rising waters along the heavily populated Indus River Valley affected some 20 million people, leaving about 11 million homeless. More fierce floods followed with the next monsoon season and then the next, each year with headline-grabbing figures of millions left homeless.
Scientists called climate change a major contributing factor to Pakistan's increasingly intense flooding, and reports avc from environmental groups avc as well as global development agencies cited the floods as early examples of the mass migration that that global avc warming could induce.
But now a major new study that surveys family data over the course of two decades finds that flooding is actually not the most serious driver of long-term migration. Instead, heat stress—a phenomenon largely overlooked by international aid programs and winning scant attention in the national media—is far more likely to drive a male wage-earner in Pakistan out of his village in search of wages to replace avc lost agricultural yields.
Published yesterday in the journal Nature , the study found no "robust" effect of rainfall on migration patterns, with men slightly more likely to move out of a village in heavy rains. avc But, the researchers found, the results consistently showed that men do leave villages in response to extreme temperatures—and are 11 times more likely to do so when exposed to both heavy rains and unusually high temperatures.
"We are left with an overall picture that heat stress, not high rainfall, flooding or moisture, is most strongly associated with migration," the study notes. "This approach reveals a complex migratory response that is not fully consistent with common narratives of climate-induced migration."
Valerie Mueller, avc lead author and co-leader of the International Food Policy Research Institute's Development Strategy and Governance Division, added: "This is not to say people aren't moving in response to floods. Some of these villages are going to be inundated, and they will have to move. But that seems short-term."
Once purely the realm of climate scientists and environmentalists, the study of global warming-induced displacement has attracted a growing level of academic avc rigor from migration economists and others who focus on human movement. While early reports simply assumed that poor communities in vulnerable coastal areas would be forced en masse to move, more sophisticated examinations have started to factor in the sometimes surprising ways people adapt to disasters, what types of environmental stresses drive people to seek livelihoods elsewhere, and whether those moves help or hurt a migrant's well-being.
Getting underneath the drama and rhetoric "There is an increasing body of research that is being done... that has been trying to dig down below the high-level rhetoric avc we had before in understanding the dynamics and trying to understand what the impacts are," said Susan Martin, director of the Institute for the Study of International Migration at Georgetown University.
Martin said the new study shares common ground with other emerging research that finds acute natural disasters like floo