Arctic sea ice will be below average again this year

Geez, I hate to keep hitting this theme, but y’know what? It’s important.

Using a fleet of Earth-observing satellites, the European Space Agency is reporting that the ice in the Arctic circle is already retreating considerably, and will once again be below average in extent this summer. This has been going on for a few years now, which isn’t terribly surprising considering that global warming is real and that we keep seeing recent years tied or exceeding records as hottest years on record.

Here’s the map they made showing sea ice extent from June 1 to August 24, 2011:

Yikes. Back in 2007, the Northwest Passage became entirely navigable by sea (without using an icebreaker ship) for the first time in recorded history. It had already been thinning for years, but an icebreaker ship was still needed to get through all of it — that’s changed now.

Moreover, it’s not just that the extent — that is, the amount of area covered by the ice — has dropped, it’s also that it’s thinning, dropping in volume. The ice volume has decreased by unprecedented amounts as well recently.

What does this mean for the current …