A glacier's pace

摘要

IN AUGUST 2019 an extraordinary plaque was unveiled at Borgarfjordur, in western Iceland. It commemorates Okjokull, the first of the country's glaciers to be completely lost to climate change. Okjokull was declared "dead" in 2014, when it was no longer thick enough to flow across the landscape, as it had done for centuries. Framed as "A letter to the future", the plaque reads (in Icelandic and English): In the next 200 years all our glaciers are expected to follow the same path. This monument is to acknowledge that we know what is happening and what needs to be done. Only you know if we did it. Along with the date, the memorial carries the words "415ppm CO_2": last summer, atmospheric carbon dioxide was measured at 415 parts per million, higher than at any point since humans have lived on Earth.