Résultat de la recherche
An analysis of the July 2006 heatwave extent in Europe compared to the record year of 2003
Recent analyses have identified summer warming trends in Europe in recent decades, culminating in 2003, when mean summer temperatures were exceptionally hot over much of Europe. Mean monthly temperatures were very high in July 2003 and reached record levels in both June and August. In 2006, the mean monthly temperature for July reached a record high. Our analysis of temperature observations shows that in July 2006, as in summer 2003, maximum temperatures were more abnormal than minimum values. The 2006 heatwave was located more to the north than in 2003, and particularly affected the Netherlands, Belgium, Germany, Poland, France and Switzerland. The July 2006 anomalies were similar in magnitude to those of June and August 2003, but the discrepancy between minimum and maximum temperature anomalies was larger in 2006 compared to both June and August 2003. For maximum temperature, the affected land area by anomalies higher than 4-6 K was largest in July 2006, although the anomalies were higher in June and August 2003 at the most anomalous sites. In the north of Europe, the absolute monthly temperature values were higher in July 2006 compared to both June (also on the Iberian Peninsula) and August 2003.
Summer 2003 maximum and minimum daily temperatures over a 3300 m altitudinal range in the Alps
The summer of 2003 was extremely hot in Western Europe and in the Alps. Here I analyse the role of elevation in the temperatures measured in 2003, and I compare daytime and nighttime values. Records from 16 stations at varying elevations show that, during the night, there was a significant correlation between heat and altitude. Hot nighttime temperatures were particularly frequent at low elevation. The frequency of unusually hot daytime highs was not correlated with altitude, but with the average degree of insolation of the sites. Compared to long-term averaged values (1961-1990) the temperatures were hottest in the normally sunniest sites. The unusual nature of the 2003 heat wave was not the absolute daily extreme values, but the lack of cool temperatures and the large number of very warm days. Averaged over all climate stations, half of the days in summer were hotter than the 90th percentile (climate normals 1961-1990), with up to 72% at some stations.