Résultat de la recherche
Changes in daily and nightly day-to-day temperature variability during the twentieth century for two stations in Switzerland
An analysis of day-to-day variability was performed on two century-longs daily minimum and maximum temperature series from Switzerland. Warmer temperatures during the 20(th) century have been accompanied by a reduction in day-to-day variability, particularly for minimum temperatures and for winter. There is a significant negative correlation between day-to-day variability and the skewness of the temperature distribution, particularly in winter and for minimum temperatures. Lower variability is linked to a reduced number of cold days and nights. Higher NAO index values tend to be associated not only with warmer temperatures but also with lower day-to-day variability. This paper confirms that the temperature warming during the 20(th) century has happened mainly through the loss of the coldest part of the series, not only in the 24-hour or yearly cycle, but also through the loss of the coldest episodes in each month.
Changes in sunshine duration are correlated with changes in daily temperature range this century: An analysis of Swiss climatological data
Analyses of the relationship between trends in daily temperature range and those of sunshine duration in the Swiss Alps show a strong correlation at lower elevation sites. The decrease in daily temperature range is associated with a corresponding decrease in sunshine duration. At high elevations, however, this relationship is absent. The decrease in daily temperature range observed this century at lower elevation sites is inferred to be a consequence of an increase in low-level cloudiness. Higher elevation sites lie above the low-level cloud layers and the moisture-laden lower atmospheric boundary layer and as a result do not exhibit the same trends.