Extreme Northern Hemisphere drought ‘virtually impossible’ without climate change

London
CNN
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Drought across the Northern Hemisphere this summer – this scorched earth, Dry rivers and induced mass Crop failure — was at least 20 times greater than the climate crisis, a new analysis finds.

Research released Wednesday by the World Weather Attribution Initiative found that without the climate crisis, the drought hitting parts of North America, Asia and Europe this summer would historically be a once-in-400-year event — meaning it would be a drought so severe that it only occurs once every 400 years on average.

But scientists have found that global warming from burning fossil fuels has made droughts of this magnitude a 1 in 20 year event.

Rising temperatures this summer, which contributed to droughts and killed tens of thousands of people across Europe and China, were “almost impossible” without climate change, the analysis found.

The researchers used historical data, observations and scientific modeling to compare conditions under today’s climate — which is about 1.2 degrees Celsius warmer than it was before industrialization — with an earlier climate, before the late 1800s.

“The 2022 Northern Hemisphere summer is a good example of how extreme events caused by climate change can play out over large areas over long periods of time. It also shows how a combination of different changes in weather can damage our infrastructure and overburden our social systems,” said a climate scientist at Imperial College London and one of the study’s authors. Friedrich Otto said in a statement.

“In Europe, drought conditions have led to reduced harvests. This is particularly worrying as it also destroyed crops following a climate change-induced heat wave in South Asia, and at a time when global food prices were already very high due to the war in Ukraine.

While much of the hemisphere experienced below-average rainfall this year, the analysis found that rising temperatures were the main driver of the drought.

The scientists noted that their findings were conservative and that “the actual influence of human activities may be greater” than what is claimed in the report.

Across the Northern Hemisphere this summer, extreme heat and low rainfall have led to several unprecedented events: China issued its first national drought warning; The United Kingdom Record its maximum temperature; Europe enjoyed its hottest summer; And this The water crisis has intensified in the American WestNew water drives reductions in use.

Along with the immediate danger to life, the intense heat of the summer posed serious threats to infrastructure, industry and industry. Food supplyFueling the ongoing cost of living crisis in many affected regions.

Europe was already struggling Geopolitical shocks to supply. This climate-induced shock “has exacerbated the cost-of-living crisis, compounding the impacts of the war in Ukraine,” said Morten van Aalst, another of the report’s authors and director of the Red Cross Climate Centre.

“We see the fingerprint of climate change not only in specific risks, but also in the cascading of impacts across sectors and regions,” van Aalst said.

Scientists are increasingly able to measure the link between the climate crisis and extreme weather events. They can make more accurate predictions.

The Northern Hemisphere can expect extreme temperatures — like those experienced this summer — more often, the analysis found.

“This result gives us insight into what lies ahead,” said Dominik Schumacher, researcher at the Institute of Atmospheric and Climate Sciences at ETH Zurich. “And with global warming we can expect stronger and more frequent summer droughts in the future.”

In this case, the Water scarcity, forest fire, Crop failures, High food prices And Low power supply What you have experienced over the past few months may be normal.

The study follows not only a summer of extreme weather, but also a season of devastating hurricanes and typhoons. The death toll from Hurricane Ian in the US has surpassed 100. Typhoon Noru recently swept across the Philippines, after intensifying from a Category 1 typhoon to a Category 5 in about six hours.

In November, world leaders will meet in Egypt COP27, UN Climate Change ConferenceExtreme weather events this year could increase the urgency of the discussions.

Sonia Senaviratne, a professor at ETH Zurich, said: “To stabilize climate conditions and avoid further worsening of these drought events, we must phase out the burning of fossil fuels. A further increase in global warming.”