There is clear evidence that the West Antarctic Ice Sheet is
contributing to sea-level rise. In contrast, West Antarctic temperature
changes in recent decades remain uncertain. West Antarctica has probably
warmed since the 1950s, but there is disagreement regarding the
magnitude, seasonality and spatial extent of this warming. This is
primarily because long-term near-surface temperature observations are
restricted to Byrd Station in central West Antarctica, a data set with
substantial gaps. Here, we present a complete temperature record for
Byrd Station, in which observations have been corrected, and gaps have
been filled using global reanalysis data and spatial interpolation. The
record reveals a linear increase in annual temperature between 1958 and
2010 by 2.4±1.2 °C,
establishing central West Antarctica as one of the fastest-warming
regions globally. We confirm previous reports of West Antarctic warming,
in annual average and in austral spring and winter, but find
substantially larger temperature increases. In contrast to previous
studies, we report statistically significant warming during austral
summer, particularly in December–January, the peak of the melting
season. A continued rise in summer temperatures could lead to more
frequent and extensive episodes of surface melting of the West Antarctic
Ice Sheet. These results argue for a robust long-term meteorological
observation network in the region.
Reference:
http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1671.html
