During the past few weeks, the top of the world has been burning. Vast swaths of the Arctic, from Alaska to Siberia, are on fire, with scientific agencies breaking out the term “unprecedented” to describe the situation.

To the ecologists who work in the Arctic, this pyrotechnic summer is both weird and weirdly unsurprising: This is what can happen when you get lots of very warm weather. And their expectation is that this summer isn’t a once-in-a-lifetime fluke; rather, it’s indicative of rapid changes that could alter the fabric of Arctic ecosystems, unleashing even more billions of tons of carbon into the atmosphere.

While the Arctic is no stranger to summer fires, the sheer amount of activity right now is striking. Mark Parrington, a senior scientist with the European Centre for Medium-Range Weather Forecasts, who’s been tracking the fires via satellites, said that he spotted between 250 and 300 fire “hotspots” north of the Arctic Circle most days in July — five to six times more than he typically sees.

The geographic spread of the fires is also unusual, according to Merritt Turetsky, an ecosystem ecologist at the University of Guelph in Canada. While fire activity has been average this year in the Canadian Arctic, it’s been pretty severe in Arctic Alaska and Siberia, where more than 13,000 square miles of land — an area larger than Belgium — burned this week, prompting Russia to send out military forces to battle the flames. Several small fires have also popped up on the other side of the world in Greenland.