How Climate Change Could Make the Migrant Crisis Worse

3 minute read

Scientists have for years cited extreme weather events connected to climate change as a contributing factor in the ongoing European migrant crisis. Drought and crop failure have destroyed livelihoods and driven sectarian conflict, leading to mass migration from the Middle East and Northern Africa to Europe.

The problem is about to get much worse, according to a new study in the journal Science. Researchers behind the study evaluated asylum applications submitted to the European Union from migrants in more than 100 countries between 2000 and 2014, and found a link between dramatic temperature fluctuations and migration.

As temperatures rise, researchers say unchecked climate change could drive a 188% increase in the number of refugees seeking asylum in Europe annually by the end of the century, as migrants seek to escape temperature extremes that might disrupt livelihoods and aggravate some of the world’s thorniest geopolitical conflicts. Even if a global effort slows the pace of global warming along the lines outlined in the Paris Agreement, researchers expect close to a 30% increase in the number of asylum applications.

“A majority of [climate change] damages occur in developing countries, and you might think that we in Europe or we in the U.S. are isolated from this,” says study author Wolfram Schlenker, an economist at Columbia University. “But that overlooks spillovers and how we’re interconnected.”

The research is more comprehensive than previous work looking at climate change and migration. But the threat is nothing new. Senior U.S. military officials have expressed concern about the connection since the early days of George W. Bush’s presidency. More recently, a 2014 Department of Defense report described climate change as a “threat multiplier” that breeds instability and “can create an avenue for extremist ideologies and conditions that foster terrorism.” And a 2015 paper published in the journal Proceedings of the National Academy of Sciences found that climate change had contributed to the Syrian civil war and the refugee crisis it caused.

However, President Donald Trump’s administration has paid less attention to the links between climate change and U.S. national security. Trump removed climate change from his National Security Strategy, released Monday, describing climate policies as part of “anti-growth energy agenda.”

Security experts say the Pentagon will continue to consider the effects of climate change despite Trump’s political rhetoric, but the broader U.S. shift on climate change will keep the U.S. from proactively addressing climate change in a way that could protect from a new migrant crisis. The Trump administration has said it will not consider the impact of climate change outside the U.S. when calculating the benefits of climate change policies. But, as the new research shows, the effects of climate change can quickly extend beyond borders.

“It’s short sighted,” says Schlenker. “Incidents that occur abroad come back to hurt you in your own country.”

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Write to Justin Worland at justin.worland@time.com