The study in the journal Science is the latest in a body of research that shows how weather shocks such as droughts — made worse as the planet warms — can stoke conflicts around the globe.
Depending how fast the planet warms, applications could rise by 28 to 188 percent, according to the projection by experts at Columbia University in New York.
That would mean between 98,000 and 660,000 additional asylum applications per year.
“Europe is already conflicted about how many refugees to admit,” said the study’s senior author, Wolfram Schlenker, an economist at Columbia University’s School of International and Public Affairs.
“Though poorer countries in hotter regions are most vulnerable to climate change, our findings highlight the extent to which countries are interlinked, and Europe will see increasing numbers of desperate people fleeing their home countries.”
Researchers found an apparent link between temperatures, farming and the number of asylum-seeker applications.
They looked at asylum applications to the European Union between 2000 and 2014, when the numbers averaged 351,000 per year.
When they compared application counts to weather in the applicants’ 103 home countries, they found that applications tended to rise when temperatures in each country’s farming regions deviated from 68 degrees Fahrenheit (20 Celsius) — the optimal temperature for crops — during the growing season.
“Hotter than normal temperatures increased asylum applications in hotter places, such as Iraq and Pakistan, and lowered them in colder places such as Serbia and Peru,” said the report.
Next, they combined this data with projections of future warming.
Under what is considered an optimistic scenario, an increase of average global temperatures of 1.8 C would increase applications by 28 percent by 2100 — meaning 98,000 extra applications to the EU each year.
“If carbon emissions continue on their current trajectory, with global temperatures rising by 2.6 C to 4.8 C by 2100, applications could increase by 188 percent, leading to an extra 660,000 applications filed each year,” it said.