Finally, on May 6 the weather cleared and field op’s began. We flew northwest from Alert, over a solidly ice-covered Arctic Ocean. After about 45 minutes, we finally began to see areas of open water… whew! That’s good, because we didn’t bring an ice drill with us: we were counting on either open water or thin ice to get our instruments in the water. Here you can see a zig-zaggy open water crack in the sea ice cover that’s called a “lead.” They start out small, of course, like a hairline fracture, and then sometimes grow to a mile or more across. This one’s maybe 100 meters wide. If you look carefully, you can see a little crack at the lower right connected to the bigger lead.
You might notice how much darker water is, relative to the snow/ice pack. If global warming continues, then this will make the surface of the earth in this area darker overall. This will tend to absorb more sunlight (just like dark clothes do) which will in turn cause more snow/ice melting! It’s a vicious cycle called a “positive feedback” that could accelerate the decay of the arctic sea ice and snow cover. We may be seeing the beginning of this happening now, but it’s difficult to say for sure until more years pass. The question is, Do we want to let more years pass without taking some kind of action now?