Brink HW van den ,
Selten FM ,
Doortmont DF ,
Opsteegh JD ,
Konnen GP
100 p
in Dutch
2001
Toon Nederlands
English Abstract The predictability of the European climate is
investigated on three aspects. First, for 3 GCM models (i.e. ECHAM4-OPYC3,
Hadcm3, CCCma) is determined how an enhanced greenhousegas-concentration
influences the temperature, precipitation and pressure. This influence is
determined for different spatial scales, i.e. global, regional (Europe) and
local (De Bilt). The changes are expressed in a quality number, which
compares the greenhouse signal with the capability of the models to describe
the mean and the variability of the current climate. The second aspect
considered is the way the probability density function (PDF) of the
temperature changes due to an enhanced greenhousegas-concentration. The
KNMI-model ECBilt shows for the end of this century not only a shifted, but
also a narrower PDF. Specifically investigated is the effect on cold winter
temperatures. For an event occurring once in 10 years, the shift is 1.2
WC, whereas the narrower PDF causes an extra 1.5 WC, being 2.7 WC in
total. The third aspect is the surge level at the Dutch coast. Not only
the effect of the greenhouse climate is investigated, but also is determined
if the observed record can be used for estimating the surge level belonging
to the (socially relevant) return period of 10.000 year. The research
shows that the available records of 100 year deficit considerably. For the
greenhouse climate, ECBilt indicates the excitation of so-called
'super-storms': storms of a extreme rareness, with an other
intensity-frequency relation than the extreme storms we know from the
current climate. For return periods longer than several centuries, the
statistics of the extremes for wind and surge in the ECBilt greenhouse
experiment are determined by these super-storms.
