Fourth Study Conference on BALTEX Scala Cinema Gudhjem

conditions even more challenging than previously expected.
Beniston (2004) extended a similar analysis to different
parts of Europe and found that in the latter half of this
century, summer temperatures would increase across much
of the continent leading to a “northward shift” in climatic
zones. This implies that Switzerland could, by the end of
this century, have a climate similar to that currently found in
the South of France, i.e., a “Mediterranean-type” of climate
with long, dry summers and a winter rainy season, see e.g.
Figure 2.
Figure 2. Gaussian distributions fitted to the mean summer
maximum temperature data at Basel, Switzerland, for the
1961-1990 reference period (A: Observations; A':
HIRHAM4 model results), the 2071-2100 A2 scenario
simulation (B) and the 2003 heat wave (C). This shows that
the smoothed probability density function (PDF) for
maximum temperatures in 2003 fits entirely within the PDF
projected to occur in the latter part of the 21st century, and is
well out of the range of the 1961-1990 summer maximum
temperature PDF. (Courtesy of M. Beniston)
5. The Nordic region
In PRUDENCE, the ideas already proposed in Christensen
et al. (2001) for the Nordic region will be repeated, but at a
much greater scale with a total of 9 participating RCMs.
Preliminary results indicate that although with this greatly
increased sampling size and even better coordinated
modeling efforts, there is still a surprisingly big scatter
between modeled climate change, even when only
addressing standard variables such as 2 meter temperature
and precipitation. In this paper these preliminary findings
will be substantiated and the analyses on extreme events,
like those described previously, will be carried out for a
larger ensemble of simulations than has been the case so far.
References
M. Beniston: The 2003 heat wave in Europe: A shape of
things to come? An analysis based on Swiss
climatological data and model simulations, Geophys.
Res. Lett. 31, L02202, 2004.
Christensen, J.H. and O.B. Christensen: Severe summertime
flooding in Europe, Nature, 421, 805-806, 2003.
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Christensen J.H., J. Räisänen, T. Iversen, D. Bjørge, O.B.
Christensen, and M. Rummukainen: A synthesis of
regional climate change simulations - A Scandinavian
perspective. Geoph. Res. Lett., 28, 1003-1006, 2001.
Schär, C., P.L. Vidale, D. Lüthi, C. Frei, C. Häberli, M.A,
Liniger, and C. Appenzeller: The role of increasing
temperature variability in European summer
heatwaves, Nature, 427, 332-336, 2004.