Tuesday, March 2, 2010

Minor myths: "The Arctic sea ice is almost back to normal"

The big dogs do a great job of cataloging the major denialist talking points, the ones with legs, the major hallucinations. See Realclimate's stuff and Skeptical Science's pages. But the work is never done; deniers change memes as often as they change their socks, and for the same reason: at the end of the day, they stink to high heaven.

So this is the first in an occasional series on the minor talking points of the deniers. This week: the claim that after hitting an all-time low in 2007, Arctic ice has "rebounded" and is now "near normal."

You find it on AccuWeather:

So far we have two years of recovery from the 2007 melt. Will it surpass 2007's melt or will it return to normal?


You find it in Watt's echo chamber:


In 2007 the winds caused an anomaly that has been recovering ever since.


[And star idiot Steven Goddard weighs in:]


Ice area is normal and well ahead of 2007 or 2008.


Thirty seconds of looking at the actual data gives the lie to the talking point:



We are running 720,000 square km below the mean. That's far from "normal" or even "near normal." What about the "recovery" part of the myth? Consider the yearly sea ice minimum, still, in 2008 and 2009, far below average levels:



When you look at the chart, you can see what's happened. In 2007 the bottom fell out. No one knows exactly why, but it was a record-shattering year. In the ensuing two years, the summer extent is slightly higher, but every year since 2007 has been far worse than every year prior to 2007. That's a critical point. 2007 remains, so far, an outlier, but the ice has not come back from that decline. Deniers are ignoring that in trying to imagine a recovery to near-normal levels. 2008 and 2009 were the second- and third-worst years for the Arctic ice on record.

Aficionados of idiocy will note that this is the same fallacy that denailists use to argue that 2005 hottest year on record = cooling for the past five years (Sure, and any day Kobe Byrant scores less than 81 points a game (his record, believe it or not) we can say his career is in decline).

We can expect more nasty surprises like 2007 ahead, but in the meantime, we can be buoyed by the denialists' optimistic view that any year that does not set a new record -- whether for temperature or sea ice or glacier loss or whatever -- must mean the trend has reversed itself.

2 comments:

  1. "in the meantime, we can be buoyed by the denialists' optimistic view that any year that does not set a new record -- whether for temperature or sea ice or glacier loss or whatever -- must mean the trend has reversed itself."

    Too true

    ReplyDelete
  2. First comment, as far as I know. Welcome!

    ReplyDelete