Mario Molina and Durwood Zaelke in Project Syndicate:
It is hard to imagine more devastating effects of climate change than the fires that have been raging in California, Oregon, and Washington, or the procession of hurricanes that have approached – and, at times, ravaged – the Gulf Coast. There have also been deadly heat waves in India, Pakistan, and Europe, and devastating flooding in Southeast Asia. But there is far worse ahead, with one risk, in particular, so great that it alone threatens humanity itself: the rapid depletion of Arctic sea ice.
Recalling an Alfred Hitchcock movie, this climate “bomb” – which, at a certain point, could more than double the rate of global warming – has a timer that is being watched with growing anxiety. Each September, the extent of Arctic sea ice reaches its lowest level, before the lengthening darkness and falling temperatures cause it to begin to expand again. At this point, scientists compare its extent to previous years.
The results should frighten us all. This year, measurements from the National Snow and Ice Data Center in Boulder, Colorado show that there is less ice in the middle of the Arctic than ever before, and just-published research shows that winter sea ice in the Arctic’s Bering Sea hit its lowest level in 5,500 years in 2018 and 2019.