By Steven Goddard,
The headline reads “NASA Satellites Detect Unexpected Ice Loss in East Antarctica”
ScienceDaily (Nov. 26, 2009) — Using gravity measurement data from the NASA/German Aerospace Center’s Gravity Recovery and Climate Experiment (GRACE) mission, a team of scientists from the University of Texas at Austin has found that the East Antarctic ice sheet-home to about 90 percent of Earth’s solid fresh water and previously considered stable-may have begun to lose ice.
Better move to higher ground! NASA also reported :
In 2007, NASA generated this map (below) of Antarctica showing just how hot it is getting down there in the land of Penguins.
Now I am really worried! But wait……. There are a few minor problems.
Assume for a minute that we accept the GRACE numbers. The first problem is Antarctica contains a lot of ice : 30 × 10^6 km³. At 100 km³ per year, it will take 300,000 years to melt.
The next problem is with the NASA temperature map. From the NASA article “The scientists estimate the level of uncertainty in the measurements is between 2-3 degrees Celsius.” They are claiming precision of better than 0.05°C, with an error more than an order of magnitude larger than their 25 year trend. The error bar is large enough that the same data could just as easily indicate rapid cooling and blue colors. That will get you an F in any high school science class.
And that is exactly what happened. The hot red map above was preceded by a cold blue map which showed Antarctica getting cooler. What motivation could NASA have had to change colors without mathematical justification?
NASA justified their heating up Antarctica with this comment :
This image was first published on April 27, 2006, and it was based on data from 1981-2004. A more recent version was published on November 21, 2007. The new version extended the data range through 2007, and was based on a revised analysis that included better inter-calibration among all the satellite records that are part of the time series.
As I have already pointed out, this is absurd. Their error bar is so large that they could have painted the map any color they wanted. Apparently someone at NASA wanted red.
But why are we looking at temperature trends anyway? The real issue is absolute temperatures. Some of the regions in which GRACE claims ice loss in East Antarctica average colder than -30°C during the summer, and never, ever get above freezing. How can you melt ice at those temperatures?
http://en.wikipedia.org/wiki/File:Antarctic_surface_temperature.png
I overlaid the Antarctica summer temperature map on the GRACE “melt” map, below. As you can see, GRACE is showing ice loss in places that stay incredibly cold, all year round.
The problem with GRACE is that it measures gravity, not ice. Changes in gravity can be due to a lot of different things beneath the surface of the ice. Antarctica has active magma chambers. Plate tectonics and isostasy also cause gravity changes.
We should be clever enough not to be blinded by technology. The claims that ice is melting in East Antarctica don’t have a lot of justification.
wpDiscuz
