Global rainstorms are tied to an unusually wet September

Storm Yagi devastated Asia and Storm Boris caused rain and floods in many parts of Europe, heavy flooding in the Sahel and Hurricane Helene hit Florida, making September this year an extremely wet month. But while scientists can directly link some extreme weather events to human-caused global warming, it’s too early to draw conclusions about this stormy month, according to AFP.

“There will always be extreme weather events, but their intensity is magnified by global warming, especially in terms of rainfall,” said researcher Paulo Ceppi at the Grantham Institute at Imperial College London. , said. “That may be one of the common drivers of different events in many parts of the world.”

Early indications from monthly data reveal record rainfall in the affected region. In central Europe, torrential rain accompanying Storm Boris was the heaviest on record in the region, flooding homes and farms, according to the World Weather Attribution (WWA) network of scientists. Global warming has doubled the likelihood of four-day heavy rain compared to pre-industrial times, and damage from climate change is accelerating.

Meanwhile, in the Japanese city of Wajima, authorities recorded more than 120 mm of rain per hour from Typhoon Yagi on the morning of September 21, the heaviest rainfall since comparable data began in 1929.

“Attributing different weather patterns around the world occurring at the same time to climate change is very difficult,” said Liz Stephens, head of the Red Crescent Climate Center. “But the basic principle remains that for every one degree Celsius of warming, the atmosphere can hold 7% more moisture.”

With global warming on track to exceed 1.5 degrees Celsius above pre-industrial levels, we can calculate the impact quite quickly. The summer of 2024 experienced the highest global temperatures ever recorded, beating last year’s record, according to the EU’s Copernicus climate monitoring program.

This year’s hot Mediterranean summer provides more evaporation, dumping more rain on Europe if conditions are right, causing all the moisture to pool in a few places, according to Ceppi. Global temperatures across both oceans and land were unusually high in August and September despite La Nina-like conditions developing in the Pacific, said researcher Roxy Mathew Koll of the Indian Institute of Tropical Meteorology. . High temperatures help provide more heat and moisture to strengthen the storm.

La Nina is a natural climate phenomenon that causes cooler ocean surface temperatures in the tropical Pacific Ocean, combined with changes in wind, precipitation and atmospheric pressure. In many places, especially tropical areas, La Nina produces the opposite climate impact of El Nino. El Nino heats the ocean surface, leading to drought in some parts of the world and heavy rain in others. Currently, the neutral phase is occurring, meaning neither El Nino nor La Nina have appeared.