An iceberg near Ilulissat, Greenland
Rain has fallen on the summit of Greenland’s ice sheet for the first time in recorded history, heightening concerns about the already-precarious condition of its ice. An unprecedented 6.3 billion tonnes of water pelted the ice sheet on 14 August, falling as rain and not snow for several hours. This was the third time temperatures at the summit had risen above freezing in less than a decade.