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269
GCMs. In the end of the 21 st century (Fig. 2 bottom), the
projected winter total temperature variability is significantly
reduced over northern Europe and the Alps with the largest
decrease (30-40%) over Scandinavia. The change in the
intraseasonal variability strongly dominates explaining about
80% of the total decrease while the interannual component
explains about 15%.
o C
%
11
10
9
8
7
6
5
4
3
2
1
20
10
0
-10
-20
-30
-40
-50
-60
Figure 2.
WINTER daily StdDev (CTL)
(SCN-CTL)/CTL
As Fig.1 but for winter.
5. Summary
The future projection (2071-2100) of European climate
based on the ensemble of RCA3 simulations driven by 5
different GCMs have shown an increase (up to 30%) of
daily temperature variability over central and southern
Europe in summer and a decrease (up to 40%) over northern
Europe and the Alps in winter. The simulated changes in
temperature variability (not shown) is found in the both cold
and warm tails of daily temperature distribution that, in
addition to the mean warming, leads to higher occurrence of
hot days in summer and lower occurrence of cold days in
winter. The ensemble mean enhancement of summer
temperature variability over central and southern Europe is
in good agreement with the results of Vidale et al. (2007)
and Fischer and Schär (2009) based on the ensemble of
different RCMs driven by one GCM. Also here, the change
in the mean temperature has the same sign and spatial
patterns although with different magnitudes among the
members of the ensemble. On the other hand change in the
temperature variability has only in general the same sign
while spatial patterns and magnitudes of the change strongly
depend on choice of driving GCM. It means that when we
look at regional climate changes in higher-order quantities
rather than in usual means uncertainties related to driving
GCMs become more important.
Acknowledgements
This work is part of the Mistra-SWECIA programme,
funded by Mistra (the Foundation for Strategic
Environmental Research), and of the ENSEMBLES
project funded by the EC through contract GOCE-CT-
2003-505539. The GCM groups are acknowledged for
providing models and boundary data. The model
simulations with RCA3 were performed on the climate
computing resource Tornado funded with a grant from the
Knut and Alice Wallenberg foundation. We acknowledge
the E-Obs dataset from the EU-FP6 project ENSEMBLES
(http://www.ensembles-eu.org) and the data providers in
the ECA&D project (http://eca.knmi.nl).
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