[Vision2020] Article Error: "Scan of Arctic ice dispels melting gloom, researcher says"

[Ted Moffett]

http://www.canada.com/Scan+Arctic+dispels+melting+gloom+researcher+says/3175785/story.html

This statement in the article at the website above is misleading, if I
understand the science correctly:

"Part of the problem with ice forecasting is that it based largely on data
from satellites. They are good at measuring how large an area is covered by
ice, but tell little about its thickness..."

In fact, satellites can provide data important in measuring Arctic sea ice
thickness, which is revealed in the following article, unless I
misunderstand (some of the scientific terminology used I do not understand),
which discusses data from ICEsat and GRACE satellites, and "ice thickness
calculations":

http://www.csr.utexas.edu/grace/GSTM/b4.html

*Session: B.4.a - Theme: GRACE & the Arctic*
*Title: Average and interannual dynamic topography from altimetry and the
GRACE mean geoid *
*First Author*: Ron Kwok
*Presenter*: Ron Kwok
*Co-Authors*: J. Morison

*Abstract*: We present our first estimates of the dynamic topography of the
Arctic Ocean derived from ICESat and EGM2008. EGM2008 has benefited from the
latest GRACE based satellite-only solutions, but is mixed with altimetric
estimates to the best of our knowledge. In ICESat processing, we retrieve
the ice and sea surface heights (ISH, SSH) by separating the elevation
returns from Arctic sea ice and open water. Differencing the ISH with the
local SSH gives the sea ice freeboard used in ice thickness calculations.
The sparsely sampled SSHs within the ice cover are used to estimate dynamic
topography – less than a few percent of the area of ice cover is open water.
An accurate geoid is clearly useful in minimizing the uncertainties in our
derived quantities at all length scales. We show the contributions of GRACE
data in improving the Arctic Gravity Project geoid (ArcGP-geoid) - what
looks to be long wavelength anomalies across the Arctic Basin are not longer
present. The resulting dynamic topography shows the expected relief but the
interpretation of the fields of interannual variability remains. There are
residuals in the field that may be due to uncertainties in EGM2008.

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Vision2020 Post: Ted Moffett
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