Sunday, May 30, 2010

Global Floating Ice In “Constant Retreat”???

I don’t know what to make of this one. I was wandering the web when I came across a Reuters article about a scientific study called “Global Floating Ice In “Constant Retreat”: Study“.

The Reuters article opens with this arresting text (emphasis mine):

LONDON

Wed Apr 28, 2010 1:38pm EDT

(Reuters) – The world’s floating ice is in “constant retreat,” showing an instability which will increase global sea levels, according to a report published in Geophysical Research Letters on Wednesday.

Floating ice had disappeared at a steady rate over the past 10 years, according to the first measurement of its kind.

“Hello,” sez I, “how can the sea ice be in constant retreat?” I knew from my previous research that the global ice was not in any kind of retreat at all.

I was also suspicious because of the next part of the quote:

“It’s a large number,” said Professor Andrew Shepherd of the University of Leeds, lead author of the paper, estimating the net loss of floating sea ice and ice shelves in the last decade at 7,420 cubic kilometers.

I went off to find the actual paper, and discovered a curious thing.

So what did I discover … and why is their quote suspicious?

Let me start with why their quote is suspicious. It is their claim that the earth has lost 7,420 cubic kilometres of ice. As I have mentioned elsewhere, when I see numbers I automatically do an “order of magnitude” calculation in my head to see if they are reasonable or not.

I knew from my previous research that there is about twenty million square kilometres (km^2) of floating ice on the planet. I also knew that much of it out towards the edges is only a metre or two thick.

So if the ice averaged say 1.5 metres thick out at the edges where the loss happens, a seven thousand cubic kilometer loss would mean a total loss of ice area of about five million km^2, or a quarter of the area of the world’s floating ice. I think someone would have noticed that before now …

Of course, that made me wonder if the problem was in the study, or in the Reuters quote. However, that same number (7,420 cubic kilometres lost) appeared in no less than 81 other online publications. So I went haring off to find the article.

One of publications reporting the story, NewScientist, 5 May, 2010, gave the “doi:” for the article. The DOI is the “Digital Object Identifier”, and it should link directly to the article, which was supposed to have been published by Geophysical Research Letters (GRL) on Wednesday, April 28th … but the curious thing I discovered was that the DOI didn’t work.

Someone had commented on that, saying “The DOI doesn’t work.” This was replied to by someone called Marshall, from newscientist.com, who said:

Hi Eric, it’s because the article hasn’t been published on GRL’s website yet. The DOI is taken directly from our press copy of the paper, so once the article is published it should work.

OK, fair enough … although the original Reuters article was allegedly published on April 28, and today is May 28, and the DOI still isn’t working. So I went to the GRL web site to see what I could find.

I first did a search for any articles by “Shepherd” in “GRL” for “2010″, and I got this:

Figure 2. Ooooops …

Thinking it might have been misfiled, I searched through all of the May articles for anything by Shepherd. Nil. I looked through the May articles for anything regarding “ice”. Nada. I repeated both searches for April. Once again, zip. Niente. Nothing.

I thought “Well, maybe it appeared in another journal”. So I took a look on Google, but I found nothing. Google did find 32,500 instances of “ice in constant retreat”, of which 7,550 also contained “GRL”.

Google also revealed that the report of the study has been picked up by ABC News, NewsDaily, Yahoo News, New Scientist, Arab News, and ScienceDaily. It was featured on Joe Romm’s global warming blog “ClimateProgress”. It has been referred to in blogs and news reports from India, Australia, Russia, and China. It shows up on TweetMeme, Huffington Post, and Facebook. Even Scientific American has an article on it.

So at this point, it has gone round and round the world. It has been illustrated with all kinds of pictures of melting ice, and of global ice extent, and (inevitably) of polar bears. It has been discussed and debated and dissected around the web.

And with all of that publicity, with all those news reports, with all that discussion and debate … as near as I can determine, despite Reuters saying it was published a month ago, the study has never been published anywhere.

Not only that, but nobody seems to have noticed that the study has never been published.

Well, that’s not entirely true. Scientific American must have noticed, because they quietly removed the page where they had published the report … but it is still in Google’s cache.

One last thing. In all of that, in the frenzy to get out tomorrow’s news today, in the rush to report the latest scientific rumour, people seem to have forgotten to ask … how is the global sea ice actually doing?

Glad you asked. Here’s today’s information, from Cryosphere Today:

Figure 3. Daily global sea ice anomaly (red line) compared to 1979-2008 average. Link contains full sized image.

As you can see, as of today, the global sea ice is exactly on the line representing the 1979-2008 average. So over the last ten years, instead of a loss of 7,420 cubic kilometres, the loss has been … somewhere around zero. Go figure.

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