Publication Date:
2019-12-03
Description:
ERA-Interim reanalysis data and data of the Hadley Centre Global Environmental Model version 2
(HadGEM2) are compared with continuous meteorological observations of near-surface wind and
temperature carried out for more than 30 years at Neumayer station, situated on the Ekström Ice Shelf of
Antarctica. Significant temperature correlations between Neumayer climate and the climate of both the
interior of the Antarctic continent and oceanic regions north of Neumayer are investigated using
observational data and model data. Mean sea level pressure fluctuations at Neumayer can be connected to
changes in the Southern Annular Mode (SAM). Shortcomings in the ERA-Interim reanalysis data with
spurious trends of up to 7 °C over 31 years are identified at several places in Antarctica. Furthermore, it is
shown that katabatic winds in both the ERA-Interim reanalysis data and in the HadGEM2 climate model are
underrepresented in frequency and speed, presumably due to the problems in representing topography in
these relatively coarse resolution models. This may be one reason for the positive 2m air temperature bias of
3 °C in the models at Neumayer station. The results of this study reemphasize that climatic trends in regions
with a low station density can not be assessed solely from model data. Thus, it is absolutely necessary to
maintain polar observatories such as Neumayer station to quantify climate change over the Southern Ocean
and Antarctica.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
Format:
application/pdf