Climate Change Doubles Europe's September Rainfall Risk

The air grew heavy with anticipation, a tangible dread clinging to the atmosphere as torrential rain lashed down across Central and Eastern Europe. The deluge, a relentless assault on the land, left behind a trail of devastation, with the town of Nysa, southwestern Poland, bearing the brunt of the fury. But this was no ordinary storm. A chilling new study revealed that human-caused climate change had played a sinister role, doubling the likelihood of this devastating rainfall.

The storm, christened Boris, unleashed its fury across the region, dropping as much as two-thirds of some cities' annual rainfall in a mere few days. The ensuing floods claimed 24 lives, a stark reminder of the escalating power of nature's wrath. Yet, amidst the devastation, a glimmer of hope emerged. Early warnings from weather forecasters allowed many cities to brace themselves, and infrastructure improvements helped shield residents from the worst of the deluge. This, according to Maja Vahlberg, a climate risk consultant with the Red Cross Red Crescent Climate Centre, was a testament to the growing resilience of some European communities in the face of climate change.

Vahlberg, a key contributor to a new analysis published by the World Weather Attribution (WWA) group, underscored the stark reality of climate change's impact. The study revealed that human activity had not only doubled the likelihood of the intense rainfall but also intensified the deluge by at least 7%. The reinsurance company Gallagher Re estimated the flooding caused billions of dollars in damages, a sobering reminder of the financial burden of climate change.

Friederike Otto, a leading climate scientist at Imperial College, London, and a driving force behind the WWA, issued a stark warning: if Earth's temperature climbs to 2 degrees Celsius above pre-industrial levels, events like this would become even more likely, potentially increasing by 50% and exceeding the intensity of this year's storms. This, she emphasized, underscored the urgent need for preparedness, urging us to brace ourselves for even more intense rainfall.

The WWA team identified the storm system as a "Vb" system, a weather pattern where cold air from the north collides with warm, moist air from the south, creating a low-pressure zone. This particular system was expansive, stretching across Austria, Poland, and Romania. Unlike typical weather systems that move quickly across the region, this storm system became trapped, stalled in place for days, unleashing its relentless rain on already saturated ground, swelling rivers and lakes to overflowing.