Arctic sea ice is ebbing faster than normal, and by September it could bottom out at a very low level

This animation consists of false-color images of the Russian coast and adjoining East Siberian Sea acquired by NASA's Aqua satellite. On June 18, the offshore waters were choked with sea ice. By July 6, 2017, a lot of it had broken up. In the false-color scheme, land is green, black is indicative of open water, and ice is a light turquoise. The darker blue prominent in the June 18th image probably is indicative of melting snow and ice that's causing liquid water to accumulate. (Images: NASA Worldview. Animation: Tom Yulsman) Under frigid winter conditions, the Arctic's floating lid of sea ice typically expands to a maximum extent in March. But thanks to human-caused global warming, that maximum seasonal spread of the ice has been shrinking over the years — and this past March it reached the lowest level ever observed for the month. But then, something unexpected happened: In May, sea ice retreated much more sluggishly. This prompted some people who deny the reality of humankind's impact on the climate to pounce. "ARCTIC SEA ICE BOUNCES BACK," shouted one headline (on a blog that bills itself as being dedicated to "common sense on climate change"). Well, hold on... Now we have the latest monthly report from the scientists at the National Snow and Ice Data Center, and wouldn't you know it: During June, Arctic sea ice shrank faster than average. That resulted in June's ice cover coming in at sixth lowest in the satellite monitoring era, which began in 1979. But that's not the most newsworthy part of the report. In my view, this is: By July 2, Arctic sea ice had retreated to a particularly low level matching what was seen on the same date in 2012. That's significant because in 2012, sea ice went on to set a record that has not been broken since. During the summer of that year, ice extent dropped precipitously, and in September it went lower than ever seen before.