This year’s snowy winter has spawned a flurry of comments along the lines of, “where’s the global warming?”
It’s right where it was expected to be: on the globe. Global average temperature has been pretty much what was expected, given la Nina conditions and, yes, global warming. But that doesn’t stop people from confusing local weather with global climate.
One of the possible (some would even say likely) reasons for the snowy winter is the drastic loss of arctic sea ice. This has altered air circulation patterns, enabling cold arctic air to penetrate further south while warmer mid-latitude air climbs further north. Therefore some regions far to the north, which usually suffer bitter cold winters, have experience extreme heat waves (relatively speaking) this winter (and in fact during recent years). One such region is northeast Canada/western Greenland.
I located seven temperature stations within that area which have reasonably good time coverage which extends up to the present day: Coral Harbour, Egesminde, Fort Chimo, Frobisher Bay, Hall Beach, Inukjuak, and Schefferville. It’s straightforward to combine their data into a regional temperature estimate:
It’s also straightforward to translate temperature into temperature anomaly, to remove the annual cycle pattern in order to isolate the changes:
If it looks to you like this region’s temperature has risen dramatically over the last few years — well, it has.
We can clarify the recent warming by smoothing the anomalies, which are monthly data. Here are three ways: by computing annual averages, by a fast-response wavelet (WWZ) analysis, and by a slightly slower-responding lowess smooth:
Yes, the regional warming in this area over the last few years is quite dramatic. Some (not tamino to be sure) might even say the pattern resembles a hockey stick.
Most of the very recent warming has been due to hotter winters rather than summers. This reduces the size of the annual cycle in temperature, as shown by the wavelet analysis:
I’ve said it before, I (and many others) will say it again: just because the climate changes doesn’t mean we won’t still have weather. And there will still be regional differences in temperature patterns, sometimes quite dramatic ones.
But this much is constant: whatever happens to global climate, those who deny the reality of global warming will consistently cherry-pick local weather to suggest that it’s not real.