Researchers have said it’s with ‘extremely high likelihood’ that the current run of record-high temperatures — with 13 of the 15 warmest years having occurred since 2000 — have happened because of greenhouse-gas emissions from burning coal and oil, the Potsdam Institute for Climate Impact Research said in a statement released Monday.

In a paper released in the journal Nature, scientists tried to determine whether the recent warm years could be a result of mere chance. They estimated that the possibility of that occurring fell somewhere between a 1 in 5,000 and 1 in 170,000 chance, leading them to conclude that it was “extremely unlikely” that the warm years were a coincidence.

“These same record temperatures were, by contrast, quite likely to have occurred in the presence of anthropogenic climate forcing,” researchers wrote in their paper.

“Natural climate variations just can’t explain the observed recent global heat records, but man-made global warming can,” co-author Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research said in a statement.

This follows recent reports that 2015 was the hottest year ever recorded and the highest since 1880. Last December, scientists said the Arctic was experiencing its highest air temperatures since 1900, and was warming twice as fast as anywhere else in the world.

It puts more pressure on countries to curtail fossil fuel emissions. During the recent COP21 climate change summit in Paris, nearly 200 countries reached an agreement to limit global temperatures from rising above pre-industrial levels at below 2°C, a key threshold before scientists warn irreversible repercussions will befall the planet.