Heatwaves in Austria are becoming more frequent and longer – record values in Vienna and Eisenstadt

Record values in Eisenstadt and Vienna

Klagenfurt follows with an average of 14.2 days of heatwave in the most recent observation period, compared with only 6.1 days between 1961 and 1990. In Vienna itself, at least one heat period as defined by the current definition has been recorded every year since 1991; in the comparison period before that, there were still ten years without a heatwave.

Carlo Buontempo, director of the EU Earth observation programme Copernicus, sees a clear pattern in the statistics. „Wenn man die letzten 20 bis 30 Jahre betrachtet, sieht man insbesondere im Sommer eine Häufung solcher Hochdrucklagen, die Hitzewellen wahrscheinlicher machen“, he had explained recently.

Davide Faranda from the Climameter project stressed that the weather pattern itself is not unusual. „Was außergewöhnlich ist, ist, dass der Klimawandel den Temperaturen in Teilen Westeuropas bis zu vier Grad Celsius hinzugefügt hat“, he said this week. For Vienna, the experts put the climatic share at 1.5 degrees Celsius.

Scientific classification

Whether the increasing frequency is actually a consequence of climate change or merely a „statistische Schwankung" remains disputed among scientists, according to Buontempo. Nevertheless, the experts list in their study specific calculated temperature differences for several European cities.

For the coming days, meteorologists are meanwhile expecting a new heat load. According to the forecast, the Austrian-wide record of 40.5 degrees Celsius from 2013, measured in Bad Deutsch-Altenburg in Lower Austria, could fall on Sunday.

Outlook on the weekly record

The data from Austria fits into a European trend. During the recent heatwave, climate change shifted temperatures in parts of Western Europe upward by up to four degrees Celsius, according to Climameter's analysis. Vienna and other state capitals remain, according to the available analyses, the centers of this development.

Overall, the time series from Geosphere Austria over six decades shows a clear shift: what was once considered an exceptional phenomenon is now measurable every summer. Heat periods of more than two weeks are no longer isolated events in Vienna and Eisenstadt, but part of the new statistical norm.