Changes in the anomalies of extreme temperature anomalies in the 20th century at Swiss climatological stations located at different latitudes and altitudes

The extreme values of a particular climatological variable determine the thresholds of vulnerability of different environmental systems. Extremes of temperature, beyond a given threshold, may exert irreversible damage on ecosystems, for example, while winds exceeding a given limit will have numerous impacts on vegetation and human infrastructure. The results of the present study highlight the change in the seasonal temperature limits at different latitudes and altitudes in Switzerland. Winter minimum temperatures at high altitude sites and summer maximum temperatures at low altitude sites in the north, in particular, have changed considerably during the last decade. Since annual extremes are seen to occur either during summer or winter, and much less during the intermediate seasons of spring and autumn, the change in summer and winter extremes are likely to have a significant impact on a number of biospheric, cryospheric, hydrologic and managed systems.