P1.12
Surface and mid-tropospheric climate change in Antarctica
David H. Bromwich, Ohio State Univ., Columbus, OH; and A. Monaghan and S. R. Colwell
Near-surface air temperatures and 500-hPa temperatures over Antarctica for 1960-2007 have been reconstructed over the entire continent using manned station observations and radiosonde records, respectively, from the READER database maintained by British Antarctic Survey. The 50-year trends found in our near-surface temperature reconstruction agree with recent work by others using a variety of spatial extrapolation techniques. It is found that the statistically significant Antarctic Peninsula near-surface warming on an annual basis has spread into West Antarctica reaching as far as east as the Pine Island Bay-Thwaites Glacier region. The warming is most marked in recent years with 2007 being the warmest year in the 1960-2007 period. In contrast to the western (eastern) Antarctic Peninsula warming which is maximized in winter (summer), the warming over West Antarctica is maximized in the spring (SON) and in that season statistically significant warming stretches across all of West Antarctica and into northern Victoria Land. Weak near-surface warming is found over East Antarctica and the continent as a whole on an annual basis although continental warming in the spring is statistically significant and driven largely by the strong and widespread changes in West Antarctica. The 1960-2007 500 hPa temperature reconstruction is qualitatively similar to that at the surface, being strongest in winter and spring. The midtropospheric results are consistent with Turner et al. (2005), who found strong winter warming in radiosonde records over Antarctica for 1971-2003 but noted greater uncertainty over West Antarctica where there are few observational constraints.
Poster Session 1, Posters
Monday, 18 May 2009, 5:00 PM-7:00 PM, Wisconsin Ballroom
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