US Releases Arctic Ice Images

July 28, 2009

Reuters has a report on the release by the US government of a series of images, taken by intelligence satellites, of Arctic sea ice coverage at six sites around the Arctic Ocean, and some additional sites in the United States.

Some 700 images show swatches of sea ice from six sites around the Arctic Ocean, with an additional 500 images of 22 sites in the United States. The images can be seen online at

The images were released following a recommendation to do so by the National Academy of Science, in order to contribute to the study of climate change.  This is noteworthy for at least two reasons:

  • These images have much higher resolution than the best previously available unclassified data.  The new images have a resolution of about 1 meter, compared to 15-30 meters in the older images.
  • The images were released on the same day as the NAS report, an uncommonly quick response for a government agency.

The higher resolution allows smaller features to be identified that, while not significant individually, may collectively be quite important in understanding and modeling the processes that lead to ice formation and melting.

For example, during the summer months, pools of melted water form on top of Arctic ice floes, and these puddles can stretch across 30 meters. The water in the puddles is dark and absorbs heat, as opposed to the white ice all around them, which reflects heat.

This is actually an instance of a larger problem that affects not only the analysis of climate change, but more prosaic things like weather forecasting.  The physical processes that contribute to the weather, for example, are reasonably well-understood, and can be described, typically, by systems of differential equations.  One of the standard approximation techniques for solviing these equations is the replacement of the differential equations with difference equations on a grid (3-dimensional, in this case).  This method works well when data can be observed and measured across the grid; but in the case of weather, there are many points where the data is missing.

Regardless of one’s view of global warming, the availability of more specific evidence has got to be a good thing.

GPS Spellcheck ?

July 28, 2009

I have mentioned here occasionally  the danger that people can become entirely too dependent on their electronic gadgets and gizmos.  So I was amused to read a story on the Reuters “Oddly Enough” page about a Swedish couple vacationing in Italy, who wanted to visit the Isle of Capri, and the famous Blue Grotto.  Unfortunately, they mistyped the name of their destination into their GPS navigation system, and ended up in the Northern Italian town of Carpi, instead:

“It’s hard to understand how they managed it. I mean, Capri is an island,” said Giovanni Medici, a spokesman for Carpi regional government, told Reuters Tuesday

It seems that other parts of their pre-trip research were a bit lacking, too.  The mistake was discovered when they asked at the local tourist office how to drive to the Blue Grotto.  It’s been a while since I was there, but I’m pretty sure it is still a cave opening to the Gulf of Naples, and is accessible only by boat.

Fortunately, the couple appeared to take the news in good grace, and turned around to drive south.

Microsoft Security Updates, 28 July

July 28, 2009

As previously announced, Microsoft today released two urgent security patches outside of its regular monthly update cycle.  The patches are described in an updated version of the Security Bulletin Summary for July, which also has download links for the installation packages.  (These fixes are also available via Windows Update.)

One of the patches (MS09-035) corrects a flaw in the Active Template Library for Visual Studio, one of Microsoft’s development tools; the associated Security Bulletin gives details.  The second patch (MS09-034) is much more important for most users; it fixes a vulnerability rated Critical for all supported versions of Internet Explorer on all desktop versions of Windows.  Because of the integration of Internet Explorer with other Windows components, and the fact that the update replaces a number of dynamic link library (.DLL) files that may be used by other applications, I recommend installing this update as soon as possible.

Adrien de Beaupré, at the SANS Internet Storm Center, has posted  a note with some further details.

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