2.2 SIMULATION RESULTS OF THE REGIONAL CLIMATE MODEL ...

Temperature
Since the changes for temperature are predetermined by the underlying model
philosophy, temperature need not be discussed here. We mention only that the
spatial structures of the temperature distribution are unchanged in the simulation.
Relative humidity
The spatial structures of the annual mean of relative humidity shows approximately
the same structure for both investigation periods, although at a different level. The
mean level for the period 2046/55 is 3% lower than for the reference period
1951/2000. But the relative humidity in the mountains and the northern part of the
investigation area is greater than for the other parts of the Elbe basin. In the drier
areas, particularly, there is a tendency that this situation is further intensified. The
spatial structures are retained both in summer and in winter. However, a much
greater decrease can be seen in summer than in winter.
Water vapour pressure
The spatial structures of the annual mean values of vapour pressure mirror the
geographic and orthographic features of the investigation area both for the reference
and the scenario periods (higher values in the NW, lower values in the mountains).
The vapour pressure increases slightly for the whole investigation area in the
scenario period, in summer more than in winter.
Sunshine duration
A significant increase in sunshine duration can be seen for the summer in the
scenario period. There are regions where it increases by 1.5 hours per day. In winter
there are negligible changes only.
Cloud cover
Similarly to sunshine duration, the amount of cloud cover is spatially only weakly.
Inversely to sunshine duration, the annual mean cloud amount decreases for the
scenario period, with a considerably stronger decrease in summer than in winter, but
with some regions even showing a slight increase.
Global radiation
For global radiation, the scenario period shows greater spatial differentiation than the
reference period. Overall global radiation increases, with the trend being much
stronger in summer than in winter.
Wind velocity
Wind velocity declines in summer for almost the whole investigation area. In winter,
however, an increase can be observed.
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