Fires in the Arctic are not solely a regional issue, as shown by the hazy skies in Switzerland last summer despite otherwise sunny weather. Smoke from major fires in northern Canada crossed the Atlantic and reached Europe. Until now, large-scale studies of Arctic tundra fires have focused primarily on rising temperatures and drought as the main drivers. The role of human activity has received much less attention, even as industrial development, settlements, roads and other infrastructure expand rapidly in parts of the Arctic, particularly in connection with extractive industries such as oil and gas production and mining.