Shomporko Online News Desk: Extreme rainfall has caused devastating flooding in western Germany and Belgium, prompting many in Europe to wonder if climate change is to blame.
Climate change, according to scientists, will result in higher rains. However, scientists cautioned on Friday that identifying its impact in last week’s continuous downpours will take at least many weeks of inquiry.
“Floods happen all the time, and they happen at random, like tossing the dice. Ralf Toumi, a climate scientist at Imperial College London, stated, “But we’ve changed the chances on tossing the dice.”
Since the rainfall began, water has burst riverbanks and cascaded through communities, toppling telephone towers and tearing down homes along its path. At least 157 people have been killed and hundreds more were missing as of Saturday.
The deluge shocked many. German Chancellor Angela Merkel called the floods a catastrophe, and vowed to support those affected through these “difficult and scary times.”
In general the rising average global temperature – now about 1.2 degrees Celsius above the pre-industrial average – makes heavy rainfall more likely, according to scientists.
Warmer air holds more moisture, which means more water will be released eventually. More than 15 centimeters of rain soaked the German city of Cologne on Tuesday and Wednesday.
“When we have this heavy rainfall, then the atmosphere is almost like a sponge – you squeeze a sponge and the water flows out,” said Johannes Quaas, professor of Theoretical Meteorology at Leipzig University.
A 1-degree rise in average global temperature increases the atmosphere’s capacity to hold water by 7 per cent, climate scientists have said, raising the chance of heavy rainfall events.
Other factors including local geography and air pressure systems also determine how specific areas are affected.
Geert Jan van Oldenborgh of World Weather Attribution, an international scientific network that analyzes how climate change might have contributed to specific weather events, said he expected it could take weeks to determine a link between the rains and climate change.
“We’re quick, but we’re not that quick,” said van Oldenborgh, a climate scientist at the Royal Netherlands Meteorological Institute.
Early observations suggest the rains might have been encouraged by a low-pressure system parked over western Europe for days, at it was blocked from moving on by high pressure to the east and north.
The floods follow just weeks after a record-breaking heatwave killed hundreds of people in Canada and the United States. Scientists have since said that extreme heat would have been “virtually impossible” without climate change, which had made such an event at least 150 times more likely to occur.
Europe also has been unusually hot. The Finnish capital of Helsinki, for example, just had its most scorching June on record since 1844.
This week’s rains have smashed rainfall and river-level records in areas of western Europe.
Though researchers have been predicting weather disruption from climate change for decades, some say the speed with which these extremes are hitting has taken them by surprise.
“I am scared that it seems to be happening so quickly,” said Hayley Fowler, a hydro-climatologist at Newcastle University in Britain, noting the “seriously record-breaking events all over the world, within weeks of each other.”
Others said the rainfall was not such a surprise, but that the high death toll suggested areas lacked effective warning and evacuation systems to cope with extreme weather events.
“Rainfall doesn’t equal disaster,” said Imperial College London’s Toumi. “What’s really disturbing is the number of fatalities. … It’s a wake-up call.”
The European Union announced a slew of climate regulations this week with the goal of halving the bloc’s global warming emissions by 2030.
According to Stefan Rahmstorf, an oceanographer and climate scientist at the Potsdam Institute for Climate Impact Research, cutting emissions is critical for slowing climate change.
“We already live in a warming world, with melting ice, increasing sea levels, and more intense weather. That will be with us for centuries to come,” Rahmstorf remarked. “However, we can stop it from growing a lot worse.”