Antarctica hasn't warmed as much over the last century as climate models had originally predicted, a new study finds.
The new study, detailed in the April 5 issue of the journal Geophysical Research Letters, marks the first time researchers have been able to give a progress report on Antarctic climate model projections by comparing climate records to model simulations (these comparisons have been done for the other six continents).
Information about Antarctica's harsh weather patterns has traditionally been limited, but temperature records from ice cores and ground weather stations have recently been constructed, giving scientists the missing information they needed.
"This is a really important exercise for these climate models," said study leader Andrew Monaghan of the National Center for Atmospheric Research in Boulder, Co.
Monaghan and his team found that while climate models projected temperature increases of 1.4 degrees Fahrenheit (0.75 degrees Celsius) over the past century, temperatures were observed to have risen by only 0.4 F (0.2 C).
The gap between prediction and reality seemed to be caused by the models overestimating the amount of water vapor in the Antarctic atmosphere. The cold air over the southernmost continent handles moisture differently than the atmosphere over warmer regions.
The models did, however, correctly capture the increases in snowfall over Antarctica in the late 20th century, followed by a decrease in the last decade.
One reason that Antarctica hasn't warmed as much as other parts of the globe is the existence of the ozone hole overhead: It alters wind patterns, creating a swirling belt of winds around the landmass that keeps comparatively warm air from seeping in, preserving the continent's frigid temperatures.
Source: Xinhua/Agencies
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