Record Rainfall in Lower Austria Last Year: Forecasts Improved
According to figures from Geosphere Austria, the five-day total rainfall record was almost shattered in St. Pölten. Improved models and a broader data base, however, facilitated forecasts and possibly prevented even worse outcomes, Klaus Haslinger from Geosphere Austria reflected in an APA interview.
Lower Austria - as well as Upper Austria, Vienna, and parts of other federal states - was hit by heavy rain, especially from September 12 to 16, 2024. On average, Lower Austria recorded a five-day rainfall amount of 212 liters per square meter. This corresponds to 2.7 times the amount that normally falls in the entire month of September in the state. Individual stations also showed return periods of more than 100 years. Locally, and especially south of the Danube, higher rainfall values were recorded than during the floods of 2002.
St. Pölten was particularly affected. In the state capital, a rainfall amount of 409 liters per square meter was recorded within five days. The previous highest value since measurements began in 1947 was 207 liters, reached in June 2009. With 417 liters per square meter, the Lilienfeld/Tarschberg station recorded even more rainfall than St. Pölten last September. Measurements have been taken here since 1992, with the previous record being 273 liters from July 1997.
Situation Similar to a Vb Weather Pattern
The trigger for the heavy rainfall was a situation similar to a Vb weather pattern (pronounced: 5b). These are low-pressure systems that move from the western Mediterranean over Italy, Austria, and Hungary further to Poland. However, the latter, the move to Poland, did not occur last year, Haslinger specified. Vb weather patterns often lead to flooding, characterized by very prolonged and intense rain. Climate change also plays a role here, the expert emphasized. There is five to ten percent more rainfall in such events than in pre-industrial times. "Climate warming, higher air and higher sea surface temperatures" are partly responsible for this.
Compared to previous flood events, there has been a leap forward in terms of protective measures and forecasting capabilities, according to Haslinger. It was "a collection of things that went better." The Danube is "already very well protected" through various measures, measures taken on the Kamp "naturally also helped," and flood areas have been "significantly reduced."
Due to improved models and a more extensive data base, forecasts have become more precise. "This will continue in the future, we hope." In general, however, an extreme event remains difficult to predict. "The crux is that outliers, due to the multitude of influencing factors that can make an event extreme, are always uncertain in their representation."
(APA/Red)
This article has been automatically translated, read the original article here.