Thursday, October 10, 2024

Climate change made deadly Hurricane Helene more intense: study


By AFP
October 9, 2024

A recent study found storms as powerful as Hurricane Helene were used to be expected once every 130 years but now occur closer to once every 53 years on average

Lucie AUBOURG

Hurricane Helene’s torrential rain and powerful winds were made about 10 percent more intense due to climate change, according to a study published Wednesday by the World Weather Attribution (WWA) group.

Although a 10 percent increase “might seem relatively small… that small change in the hazard really leads to big change in impacts and damage,” said climate scientist Friederike Otto, who heads the research organization.

The study also found that fossil fuels — the primary cause of climate change — have made hurricanes like Helene 2.5 times more likely to occur.

In other words, storms of Helene’s magnitude were formerly anticipated once every 130 years, but now the probability is closer to once every 53 years, on average.

To conduct the study, researchers focused on three aspects of Hurricane Helene: precipitation, winds and the water temperature of the Gulf of Mexico — a key factor in its formation.

“All aspects of this event were amplified by climate change to different degrees,” Ben Clarke, a co-author of the study and researcher at Imperial College London, told a press conference.

“And we’ll see more of the same as the world continues to warm,” he continued.

The research by WWA, an international group of scientists and meteorologists who study the role of climate change in extreme weather events, comes as the southeastern US state of Florida prepares for the arrival of another major hurricane, Milton, just 10 days after it was hit by Helene.



– Destruction –



Helene made landfall in northwestern Florida on September 26 as a Category 4 hurricane with winds up to 140 mph (225 kph).

The storm then moved north, causing heavy rain and devastating floods in several states, including North Carolina, where it claimed the highest death toll.

The authors of the study emphasized that the risk posed by hurricanes has increased in scope beyond coastal areas.

Bernadette Woods Placky, chief meteorologist at NGO Climate Central, said Helene “had so much intensity” that it would take time for it to lose strength, but the “storm was moving fast… so it could go farther inland pretty quickly.”

This study utilized three methodologies to examine the three aspects of the storm, and was conducted by researchers from the US, the UK, Sweden and the Netherlands.

To study its rainfall, researchers used an approach based on both observation and climate models, depending on the two regions involved: one for coastal areas like Florida, and another for inland areas like the Appalachian mountains.

In both cases, the study found precipitation had increased by 10 percent because of global warming, which is currently at 1.3 degrees Celsius above pre-industrial levels.

To study Helene’s winds, scientists looked at hurricane data dating back as far as 1900.

They determined Helene’s winds were 11 percent stronger, or 13 mph (21 kph), as a result of climate change.

Lastly, the researchers examined the water temperature in the Gulf of Mexico, where Helene formed, finding it was around 2 degrees Celsius above normal.

This record temperature was made 200 to 500 times more likely due to climate change, the study asserts.

Warmer oceans release more water vapor, providing more energy for storms as they form.

“If humans continue to burn fossil fuels, the US will face even more destructive hurricanes,” Clarke warned in a statement.


A US climate scientist sees hurricane Helene’s devastation firsthand



By AFP
October 9, 2024

With at least 230 people killed, Helene is the second deadliest hurricane to hit the continental United States in more than half a century 


Ulysse BELLIER

Carl Schreck spent his career studying tropical storms thousands of miles away from home.

But when Hurricane Helene hit the American climate scientist’s hometown in North Carolina and flooded several of his friends’ homes, the shocking experience made him rethink his research priorities.

“I know how devastating the rainfall in hurricanes can be, but like to actually know people… that are affected by it — it is, it’s really heartbreaking to see,” Schreck told AFP from his home near Ashville, the epicenter of the disaster that ravaged the southeastern United States.

As another major hurricane, Milton, was barrelling toward Florida, a study released Wednesday by the respected World Weather Attribution concluded that Helene’s destructive force was exacerbated by climate change.

Schreck, a scholar at the Institute for Climate Studies at North Carolina State University, and his colleagues had been studying Helene’s formation in the Caribbean for days — until it pummeled Asheville on September 26-27.

Several of Schreck’s friends saw their houses destroyed, while a family he knew died in the flooding.

“It’s been over 100 years since we’ve seen something like this,” said Schreck, whose own house was spared. “So it’s been a very tragic experience for our community.”



– ‘Irony’ –



With at least 230 people killed, Helene is the second deadliest hurricane to hit the continental United States in more than half a century after Katrina, which ravaged the state of Louisiana in 2005, claiming nearly 1,400 lives.

But amid the immense material damage, another misfortune befell the community in Asheville: a major climate data center, which shares the building with Schreck’s facility, lost power in the storm, and its crucial data is currently inaccessible to scientists worldwide.

“That’s one of the real ironies of this event,” said Schreck. “We collect all of the world’s weather and climate data right here in Asheville, going back more than 100 years, and power was cut off to that.”

Emergency workers are having to pump water into the center’s water cooling system from a fire truck to cool down the computers.

The National Oceanic and Atmospheric Administration (NOAA), which manages the center, says it is working “to minimize the risk of any potential data loss,” but gives no timeline for when the center will resume operations.



– Communicate better? –




As soon as cellphone service was restored in the region following Helene, Schreck and his colleagues got to work.

“There has been a lot of discussion about, like, what does this mean for climate change?” Schreck recalled. “What’s going on with our community? Why was this so severe? How could we have communicated it better?”

Although Helene struck Florida first, it was in the Appalachian mountains more than 500 kilometers from the coast where the vast majority of deaths occurred, mainly due to torrential flooding.

Inland rainfall, “is one of the most dangerous parts of a hurricane that usually doesn’t get enough attention,” he said. “And that’s something that’s… getting worse with climate change.”

“I’ve always been really interested in how hurricanes affect rainfall and flooding,” he added. “So that’s something I’m really gonna be looking at even more going forward.”

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