Glaciologists ride to the rescue: Greenland mistake corrected in peer-reviewed paper
- 08 May 2012, 14:13
- Verity Payne
Remember last year's
furore over the mistake by the Times World Atlas which
suggested that Greenland had lost 15 per cent of its ice in little
over a decade?
Now the group of the scientists who first called the Atlas out
on their dodgy calculations have just published a peer-reviewed
scientific paper which offers a more realistic assessment of the
rate of Greenland ice loss.
In case you've forgotten what all the fuss was about, here's a
quick re-cap:
HarperCollins put out a press release in September last year for
the 2011 edition of the Times Comprehensive Atlas of the World
stating that since 1999 "15% of the permanent ice cover (around
300,000 sq km) of Greenland, the world's largest island, has melted
away".
The 15 per cent figure, reportedly calculated by comparing the
Times Atlas maps of Greenland from 1999 and 2011, was fairly
widely
covered in the media until polar scientists pointed
out that the figure was wildly at odds with in-situ and
satellite measurements of Greenland ice cover. The Times Atlas maps
also showed areas of Greenland as ice-free when they are in reality
covered by ice.
As Poul Christoffersen of the University of Cambridge Scott
Polar Research Institute
wrote at the time;
"...[S]cientists are well aware that one
big error can cloud a thousand truths."
And indeed journalist Christopher Booker was quick to try to use
the episode to further
his own dubious narrative about man-made climate change, as we
reported at the time.
HarperCollins eventually retracted the 15 per cent claim, but
quibbled over whether their maps were accurate. The scientists kept
up pressure, and ultimately HarperCollins worked with polar
scientists to
correct the Times Atlas map of Greenland.
Last week a peer-reviewed
assessment of the matter was published in new open access
journal 'The Cryosphere'. The paper sums up current scientific
knowledge of Greenland ice shrinkage and specifically references
the Atlas affair, with the authors finding that:
"Greenland has not lost 15 % of its ice
area since 1999 [as claimed by the Times Atlas], but it has
exhibited net ice loss."
They find that Greenland glaciers of all types are losing ice
overall, and that ice loss from many glaciers is accelerating. The
ice loss is not steady, however, as there is year on year
variability in glacier shrinkage. For the whole of Greenland, they
estimate that glaciers are shrinking at a rate:
"[O]ne or more orders of magnitude less
than in the Times Atlas."
The polar scientists also find that an area of eastern Greenland
shown as ice-free by the original Times Atlas maps actually
contains some 50,000 square kilometres of ice, and is shrinking at
a rate of roughly 0.019 per cent per year.
The publication of this paper provides a considered
peer-reviewed response to a very public error. It also highlights
just how important it is that scientists immediately protest
obvious scientific inaccuracy in the public realm.
Solely relying on a response via peer-reviewed paper would have
been inadequate in this case, because of how long the peer-review
process takes - the paper was submitted in October last year and
only published last week.
Thankfully, the scientists' swift reaction at the time enabled
the mistake to be rectified straight away, before the erroneous
figure could spread too far.
Repeated rescues
This isn't the first time that this group of glaciologists have
come forward to correct unsubstantiated claims about glaciers. In
December 2009 the new paper's lead author
Jeffrey Kargel, University of Arizona, and co-author Graham Cogley,
Trent University, were instrumental in
correcting the inaccurate claim that Himalayan glaciers could
melt by 2035 in the 2007 report from the Intergovernmental Panel on
Climate Change.
And more recently, co-author
Jonathan Bamber, University of Bristol, pointed out that new
studies finding that some high Asian glaciers are not losing as
much ice as thought, or are even gaining ice, do not mean that the
rest of the world's glaciers have stopped shrinking - contrary to
some
sensationalist and confusing headlines.
The 'Climategate' episode
dealt a big blow to public trust in climate scientists, so it is
encouraging that this group of glaciologists show such willingness
to stand up for accurate reporting of their science, regardless of
the source of any error. They point out just how valuable such a
response can be, saying:
"The publisher corrected the mistake
quickly because the scientific community reacted immediately to the
incorrect description of climate-related change in public media. We
hope that as a result public trust in science is strengthened."