Dick Lindzen recently observed, as he often has, that there is no obvious trend in Arctic or Antarctic ice cover. This provoked a shriek of vituperative rage from a Warmist site — a site which in its header quotes Leonardo Di Caprio as an authority on climate. Ya gotta laugh: An eminent climatologist is wrong about the climate but a Hollywood actor is right! You couldn’t make it up. The reality contact of these guys is so poor that they obviously don’t realize how mad they sound to all but true believers.

Unlike a lot of Warmist writing, this diatribe did however quote one piece of evidence that Lindzen is wrong — which is most refreshing. A Warmist article with more than abuse and vague generalizations about “the science” is rare.

So I thought that I would have a look at the research paper cited. The paper could however be a textbook case of how NOT to extract generalizations. It covers two unbelievably short time periods, which is exceedingly uninformative. Any student of statistics knows that in a random sequence you do get “runs”. In a series of coin tosses, for instance, you may get a series of “heads” for a short period. But if you extend your series you find that you get runs of tails too — so that overall there is no trend. You need a long series before you can extract reliable generalizations.

And the article abstracted below is clearly in the “ungeneralizable” category. The author compares, for instance, 2002–2003 with 2007–2009. And to add insult to injury, the trend is not the same in the two periods concerned! So which do you generalize from? What a crock!

Rather saddeningly, however, the article appeared in a prestigious academic journal. As we have often seen before, the pox of Warmism destroys intellectual standards.

Increasing rates of ice mass loss from the Greenland and Antarctic ice sheets revealed by GRACE

By I. Velicogna

We use monthly measurements of time-variable gravity from the GRACE (Gravity Recovery and Climate Experiment) satellite gravity mission to determine the ice mass-loss for the Greenland and Antarctic Ice Sheets during the period between April 2002 and February 2009. We find that during this time period the mass loss of the ice sheets is not a constant, but accelerating with time, i.e., that the GRACE observations are better represented by a quadratic trend than by a linear one, implying that the ice sheets contribution to sea level becomes larger with time.

In Greenland, the mass loss increased from 137 Gt/yr in 2002–2003 to 286 Gt/yr in 2007–2009, i.e., an acceleration of −30 ± 11 Gt/yr2 in 2002–2009.

In Antarctica the mass loss increased from 104 Gt/yr in 2002–2006 to 246 Gt/yr in 2006–2009, i.e., an acceleration of −26 ± 14 Gt/yr2 in 2002–2009. The observed acceleration in ice sheet mass loss helps reconcile GRACE ice mass estimates obtained for different time periods.


Posted by John J. Ray (M.A.; Ph.D.). For a daily critique of Leftist activities, see DISSECTING LEFTISM. To keep up with attacks on free speech see TONGUE-TIED. Also, don’t forget your daily roundup of pro-environment but anti-Greenie news and commentary at GREENIE WATCH . Email me here

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