Is Climate Change Causing the Deadly Floods in Europe? 

Central Europe has been plagued by intense flooding this week, killing at least 23 people, according to Reuters. While it’s difficult to draw a conclusive link between this event and climate change, experts say the most severe floods to hit the region in at least two decades fit into a broader pattern of extreme weather events. 

“Changes in the climatic condition make these severe rainfall events much more likely, so it fits into the patterns of what climate experts see, but it's very difficult to pinpoint and say that a percentage of this is down to climate change,” says Swenja Surminski, managing director of climate and sustainability at insurance firm Marsh McLennan and professor of climate risk management at the London School of Economics.

The flooding has most heavily impacted Poland, the Czech Republic, Slovakia, Austria, Hungary, and Poland, and while some countries are facing more devastation, others are starting to begin recovery. On Wednesday, volunteers and soldiers in Southern Poland tried to brace for further flooding by placing sandbags near river beds surrounding the city of Wroclaw in order to protect homes. Elsewhere, the Czech Republic reported another death due to the floods after police found the body of a 70-year-old woman who appeared to have been swept away by the waters in the Northeastern part of the country. With the exception of Southwestern Poland, the waters appear to be receding in most places, allowing authorities and residents to begin the process of cleaning up.

The floods are caused by the slow-moving Storm Boris, which has brought an onslaught of intense rain. In the last four days, the storm has dumped five times the average amount of rainfall expected in September in the region. In the worst hit areas, such as Ostrava, Czech Republic, entire homes have been submerged under water, according to aerial photographs. 

Klaus Iohannis, the President of Romania—a country that has seen at least seven deaths due to the floods—said that the severe weather is a symptom of climate change in a statement published on Sept. 14. “We are again facing the effects of climate change, which are increasingly present on the European continent, with dramatic consequences,” he wrote.

Experts say while it is too early to definitively say whether climate change directly caused or exacerbated the ongoing disaster, the flooding is consistent with the extreme weather predicted to occur more frequently due to climate change.

“It's really difficult to relate a single event to climate change impact,” says Paul Bates, a professor of hydrology at the University of Bristol who specializes in the science of flooding. Bates says that in order to definitively prove whether or not climate change contributed to the flooding in Europe, researchers will need to conduct an attribution study, which takes at least several weeks. “Every time we do an attribution study, we tend to find that the events we see have been exacerbated by climate change, and I'm pretty sure that will be the case here, but we don't yet conclusively know,” says Bates. 

Another factor that may be contributing to the severe floods, however, is human activity and land-use change. Because most of the recent floods in Central Europe are river floods, says Bates, it makes the links between the flooding and climate change less straightforward. “It’s a much less clear picture for river flooding,” he says.

Heavy rains can overwhelm rivers, making them more likely to overflow. But infrastructure decisions—be it dams and levees or new housing developments in floodplains—can play a part in how devastating, or not, that event might be.

In the meantime, as these weather patterns become more common, Surminski cautions: “This is something we need to be better prepared for.”