SIMPLE TEMPERATURE SCENARIO FOR A GULF-STREAM INDUCED CLIMATE-CHANGE

Consequences of a Gulf Stream induced ocean surface cooling for the te mperature climate of Western Europe were studied by means of a conditi onal perturbation of the observed daily temperature time series of the Netherlands. On days with advection of airmasses of maritime origin, the observed temperatures in the series were lowered with a fixed valu e, representing the influence of a cooler Atlantic Ocean. On the other days, the observed temperatures were left unchanged. The perturbation results in a decrease in the mean temperature that is almost constant over the year, and in a change in the standard deviation of the daily temperatures that is seasonally dependent. Due to preferential coolin g of warm. winter days, the standard deviation decreases in the winter , whereas in the other seasons the standard deviation increases as a r esult of preferential cooling of days with low temperatures. Although this ocean cooling scenario indicates an increase of the relative freq uency of cold winters and cool summers, it is neither characterized by the occurrence of winters with unprecedented low temperatures nor by the disappearance of summer heatwaves.