New images from space show giant swaths of melting over Antarctica in 2005. Melting is indicated in red, orange, and yellow. (Source: nationalgeographic.com)
Most studies and data collection indicate that the Arctic ice cap is melting, now a new study shows the Antarctic ice cap is also losing mass
DailyTech blogger Michael Asher recently wrote an article which indicated that Antarctica's ice cap was thickening. The article cited a study by the British Cambridge
Centre for Polar Observations. The Center's study, published in July
2006, stated that Antarctic ice mass was increasing by 27±29Gtyr-1.
The study had an admittedly large range of error that was in fact
larger than the predicted increase. The large error range was
attributed to difficulties in predicting snow density.
Another major study, which contradicts the Cambridge Centre's results was released a few months before. The study was conducted by major U.S. research institute CIRES,
a joint institute comprised of Colorado University-Boulder and the
National Oceanic and Atmospheric Administration. The study was published in the journal Science Express in March 2006.
The
study used two NASA satellites to examine the mass of Antarctica's ice
cover. The satellites would experience variable gravitational pull as
they passed over the poles, depending on the mass of snow cover. This
technique allowed the study to predict the mass of snow at the poles
much more precisely, with a smaller range of error than the Cambridge Centre's study.
The CIRES study discovered that Antarctic ice mass was actually decreasing, at a rate of 152 ± 80 cubic kilometers of ice per year. The Cambridge Centre's study actually might predict an increase or a decrease, but the CIRES study clearly reports a decrease.
Further, the CIRES study indicates the decrease in ice mass would lead to 0.4
± 0.2 millimeters of global sea-level rise per year. This would mean
that over 100 years, the loss in Antarctic ice mass would lead to
global sea level rising 4 cm, as the ice is on
bedrock. These gradually rising sea levels would likely lead to loss
of habitable land in coastal areas, such as Florida and California.
Also, the large amount of water displaced into the ocean, would likely
disrupt the ocean's currents, causing unpredictable climate changes.
Furthermore, other studies and data over recent years have indicated that large areas of Antarctic ice which had not previously thawed are now freezing and rethawing each year. This may eventually lead to even greater loss of ice mass.
As
mentioned in Michael Asher's article, there is consensus in the
scientific community that the Arctic ice cap is melting, and many
studies indicate it is melting at a rate far faster than predicted.
While
critics deride global warming and climate change models as being overly
pessimistic, it turns out they may be too optimistic in their
predictions of climate change. A more recent study
by CIRES indicates that the Arctic ice caps are melting at a rate that
is far faster than that predicted by any of the current climate
models. The actual data paints a picture of Arctic ice melt far
bleaker than that in the models.
While the melting of the Arctic ice cap
will not increase sea levels, it will destroy the Arctic biosphere. It
will most likely lead to the extinction in the wild of many species
include large mammals, such as the polar bear and various arctic
seals. This unfortunate loss of biodiversity may be an unprecedented
ecological event. If global warming is a result of human behavior--industrialization,
deforestation, and/or domestication--as many theories predict, then the
impending extinction would mark the first time a single species
single-handedly destroyed a major ecosystem.
The melting of
Arctic ice cap may not lead to sea levels rising, but the melting of
the ice cover on neighboring Greenland, certainly will. A new major ongoing study
by the University of Reading in Britain is investigating the rate of
melting. Its finding are that Greenland's average temperature only
needs to increase by 3 degrees Celsius to melt its ice-sheet, and that
significant melting is likely to occur over the next century.
The
study indicates that over 1000 years the melting of Greenland's ice
cover will raise sea levels by 7 meters. This equals an increase of
over 2 feet a century. Combined with the CIRES study's predictions for
the Antarctic melt, this means that sea levels could rise by over 3 ft
in the next century. As mentioned, this would have numerous negative
social and climatological effects.
As new studies and data
emerge, a clear picture of melting at both poles emerges. Whether we
can reverse this melting with technology, or whether we are too late
remains to be seen. However, though the cost may be high, the
ramifications of inaction may be far worse. Coastal land loss, chaotic
weather from violent thunderstorms to droughts and flooding,
and irreversible loss of biodiversity are among the dire consequences
of inaction. Admittedly, many of the details of climate change are not understood, so people need to avoid jumping to hasty conclusions, absolutely. However, the threat of these consequences and effects (good and/or bad) leaves no doubt that
this is a significant topic to the future of mankind's habitation of
Earth and much scientific research needs to be done to more precisely
understand what is causing global warming, and a creative examination of if it is within the means of modern technology to fix
it.
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