The intensity and scale of the flood Germany This week shocked climate scientists. They did not expect that records would be broken on such a large scale or so quickly.
A fatal heat wave occurred in the United States and Canada two weeks ago, with temperatures rising above 49.6 degrees Celsius and flooding in the central region. Europe It has raised concerns that man-made climate damage is making extreme weather worse than expected.
On Wednesday, the precipitation record for the vast area of the Rhine Valley was broken, with devastating consequences.at least 58 people killed, Tens of thousands of houses were flooded and electricity supply was interrupted.
Parts of Rhineland-Palatinate and North Rhine-Westphalia were inundated by 148 liters of rainfall per square meter within 48 hours, while parts of Germany usually received about 80 liters of rainfall throughout July. Rise.
After the Volm River burst its banks and the water level rose to a level no more than four times a century, the city of Hagen declared a state of emergency.
The most eye-catching among more than a dozen records Set up at Köln-Stammheim station, It was submerged by 154 mm of rain within 24 hours, erasing the city’s previous high of 95 mm of daily rainfall.
Climate scientists have long predicted that human emissions will cause more floods, heat waves, droughts, storms and other forms of extreme weather, but the recent peaks have exceeded many expectations.
Dieter Gerten, professor of global change climatology and hydrology at the Potsdam Institute for Climate Impact Research, said: “I’m surprised how much it is higher than previous records.” “We don’t just seem to be above normal, but also We did not anticipate areas in terms of spatial scope and development speed.”
Gerten grew up in a village in the affected area. He said that he would be submerged occasionally, but not like this week. The previous summer downpours were equally heavy, but the area hit was smaller, and the previous winter storms did not raise the river to such a dangerous level. “This week’s incident is completely atypical for the region. It lasted a long time and affected a wide range of areas,” he said.
Scientists will need more time to assess the extent to which human emissions make this storm more likely, but the record downpour is in line with broader global trends.
“With climate change, we do expect all extreme hydrometeorological events to become more extreme. What we see in Germany is broadly consistent with this trend.” Carlo Buontempo, Director of the Copernicus Climate Change Service Center, European Center for Medium-Term Weather Forecast Say.
The seven hottest years on record Has happened since 2014, Mainly due to global warming, which is caused by engine exhaust, forest burning and other human activities. Computer models predict that this will lead to more extreme weather, which means that records will be broken more frequently in more places.
In recent weeks, the Americas have been the focus.Canadian National Daily Calorie Record Over 5C Two weeks ago, some local records in Oregon and Washington state did the same.Scientists say it is almost impossible for these extreme events to occur at this latitude No man-made warming. Last weekend, the monitoring station in Death Valley, California Register 54.4C, Which may prove to be the highest temperature reliably recorded on Earth.
Daniel Swain, a climate scientist at the University of California, Los Angeles, said that the United States has set so many records this summer that they are no longer news: “Extreme events that should have been newsworthy a few years ago are no longer news.” t, because they look pale and feeble compared to the amazing rise a few weeks ago. He said that this has also happened in other countries, although there is less media attention. “The United States has often become the focus of people’s attention, but we have also seen abnormally high temperatures in Northern Europe and Siberia. This is not a partial freak event, it is definitely part of a coherent global model. “
Parts of Lapland and Siberia were also muggy due to record high temperatures in June. Cities in India, Pakistan and Libya have experienced unusually high temperatures in recent weeks. The suburbs of Tokyo experienced the heaviest rainfall since the start of the survey. Within a day, London received the usual one-month rainfall in July. Events that happen in 100 years are becoming commonplace. The abnormal weather is getting more and more normal.
Some experts worry that the recent shocks indicate that the climate system may have crossed the dangerous threshold. They are studying whether this trend will become more “non-linear” or more turbulent due to the chain reaction of Arctic drought or melting snow, rather than a steady rise in temperature and a steady increase in extreme events. This theory is controversial, but recent events have triggered more discussions about this possibility and the reliability of models based on past observations.
“We need to better simulate non-linear events,” Gerten said. “In recent years, our scientists have been surprised by events that happened earlier, more frequently, and more intensely than expected.”
