The floods that have hit southern Germany in recent days can be attributed to a low-pressure area over the northern Mediterranean, experts from reinsurer Munich Re said on Monday.
Damage caused by cyclones known as Genoa lows or Vb cyclones is increasing, according to data collected by the reinsurer, the world’s largest.
“They suck up water above the Mediterranean Sea and then move from northern Italy towards the Balkans,” says Munich’s chief climatologist Ernst Rauch.
“Then the exceptional nature of these Vb weather conditions is revealed. The extremely moist cloud vortex turns north, comes back and is pushed against the Alps,” Rauch said. “We then experience this pushing out of the clouds over a period of several days.”
The difference between this phenomenon and flash floods such as those that occurred further north in Germany along the Ahr Valley in 2021 is the extent over a large area and the duration of the rainfall over several days.
According to Rauch, these Vb weather conditions only occur in spring and summer. Data from the German Meteorological Service (DWD) shows that the number of Vb events has increased in recent years. Record declines have also been recorded in certain areas.
“Record precipitation is likely linked to climate change, as warmer air can hold more moisture – about 6% to 7% more moisture per degree,” the climatologist said. A link to climate change was plausible even if scientific proof was not possible, he added.
“Our data shows that damage from severe weather is increasing, and this statistic makes a link to climate change likely,” Rauch said. He called for action to find a response to the increasing damage and extreme events. “The central answer is prevention,” he said.
