by Once a synonym for leisure and kidnapping, summer has increasingly become a season that is characterized by fear and disorder. The pollution of the fossil fuels – in addition to other composite factors – has turned into a time of the assembly dismissal during these months, which was interrupted by relentless heat waves, rampant forest fires and catastrophic floods.
This summer was defined in particular by a tragic increase in fatal floods in the USA and the escalating volatility of our warming world was underlined.
It is no coincidence, this is the summer of flooding, say climate researchers say, and for 100 to 1,000 years there have been almost simultaneously in several states in several states in several days.
Large parts of the United States have seen an unusually damp summer with records in the air. When cold fronts and other weather systems enter into, this moisture can be turned out, such as a water -loaded sponge and delivers heavy and often highly localized downpours.
During the majority of summer, the atmospheric conditions in the USA led the moist air from the unusually warm Golf and the western Atlantic, including the Gulf Stream, to the north, Daniel Swain, climate researcher from UCLA, told CNN. This has an unusually high level of moisture in all atmosphere in the USA east of the Rocky Mountains, said Swain.
It has caused meteorologists to be recorded, which are referred to as exuberant water. This is the amount of rain that would result from the current extraction of the entire water in the air.
This pattern has led to one flood after another.
Omar Gutierrez, 31, helps to remove debris from the flooded dining area of the kitchen La Salsa, a Mexican restaurant, after fatal floods in Ruidoso, New Mexico, July 9, 2025. – Paul Ratje/Reuters
First and foremost, there was the devastating flood in Texas, which died in the night of July 4th more than 130 people. But the flood flood events were also concentrated elsewhere. Three people were killed in a flood of falls on July 8th in Ruidoso, New Mexico, on a forest fire scars in connection with heavy rains.
Some important streets in Chicago were suddenly under water when a 1000th anniversary event occurred in early July. In parts of North Carolina, the remains of the tropical storm Chantal led to fatal heavy rain and flooded on the same weekend as the Texas tragedy. In New York City, Water hurried to the subway tunnel when the city had the second hardest precipitation in an hour on July 14th in an hour, with widespread fall until 15th. And last week Kansas City was on July 17th.
Some of these floods resulted from rainfall that have a return frequency of around 1,000 years, which means that it has only a probability of 0.1% in a certain year. However, climate change loads the cubes in favor of an extreme precipitation.
“When we talk about e-events of e.g. 1000-year-olds, we talk about the probability of these events if there is no human warming (i.e. how often we expect it from natural variability), said climate researcher Michael Mann from the University of Pennsylvania.” Of course, these events are much more common * because * from human warming, “he said in an email.
However, his research has identified other factors, as persistent, large -scale weather patterns, which are called “atmospheric response” and can make the extreme weather, including floods, even more likely. Just as sound waves or ocean case can reinforce each other, the atmospheric response in the upper atmosphere of wavy jet stream patterns can happen, which leads to weather systems that remain in place for weeks.
A recently carried out study on which men worked has found that such weather patterns have tripled in the summer months since the mid -20th century. The problem is that these patterns “are not necessarily well recorded in climate models”, he said. This increases uncertainty through future projections for extreme weather trends.
The influence of climate change on strong rainfall is most clear when it comes to short events for a short time, as it happens repeatedly this summer.
“It is not an average rainfall that is really affected by climate change,” said Swain. “It is really mathematically correct, the more extreme the rain event, the clearer the connection to climate change.”
Tropical Storm Chantal flooded central -north Carolina with violent rain, here in Chapel Hill on July 7, 2025. – Peter Zay/Anadolu/Getty Images
According to the climate researcher Kate Marvel, physics, as the global warming affects strong rainfall events.
“This is almost a textbook example for the effects of climate change,” she told CNN. “Science behind it is so simple that you can see it in everyday life. Warm water is driving more evaporation – the bathroom becomes much more steamed than a cold after a hot bath,” she said.
“Warm air contains more water vapor – a cold beer gets wet from the outside on a hot day, because when air comes into contact with the cooler surface, it has to find out its water vapor,” said Marvel.
“Warm soil makes it easier for moist air to moisten up – that’s why thunderstorms take place on hot summer afternoons. Put them together and you will get the perfect conditions for heavy rain,” said Marvel, author of the new climate fox “Human Nature”.
“Whether a downpour turns into a catastrophic flood depends on many things: how porous the soil is, the topography of the area, the people and the things that are in danger. However, there is no doubt that climate change, which is caused by human emissions of greenhouse gases, becomes more extreme extreme extreme extreme.”
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