Why Hurricane Patricia Can't Be Blamed On Climate Change | KERA News

Why Hurricane Patricia Can't Be Blamed On Climate Change

Oct 23, 2015
Originally published on October 23, 2015 6:58 pm

On Thursday morning, Patricia was a relatively small Category 1 hurricane. By Friday afternoon, it was the most powerful storm ever recorded in the Western Hemisphere.

Is climate change to blame for this record-breaking storm's ferocious rise?

The answer is complex, and shows why it's so hard to tie a single weather event to global warming.

Between Thursday and Friday, Patricia underwent what hurricane researchers call "rapid intensification," a phenomenon by which storms gather strength at an astonishing speed.

"It's a little bit like a perfect storm; lots of things come together in order to produce rapid intensification," says Ben Kirtman an atmospheric scientist at the University of Miami.

Researchers aren't great at predicting when storms will rapidly intensify, but they do know a lot about why it happens.

Hugh Willoughby, a hurricane expert at Florida International University, says most hurricanes never reach their full potential.

"In a storm like this, everything is right," Willoughby says.

Calm, even winds allowed Patricia's structure to form and strengthen, and warm water fueled the hurricane's churning convection. That, in turn, caused its winds to more than double to over 200 miles per hour in less than a day.

The warm water that fueled Patricia is available in abundance this year. The Eastern Pacific has been very warm, thanks to an ocean phenomenon known as El Niño. This year's El Niño is likely to be one of the strongest ever recorded, says Mike Halpert of the National Oceanic and Atmospheric Administration.

"The fact that we've had a really active [hurricane] season in the Eastern Pacific — that's clearly an El Niño effect," says Kirtman.

But here's where things get fuzzy. Although El Niño involves warmer oceans, and climate change is causing ocean surface temperatures to rise, there's no definitive link between the two, says Halpert. In fact, right now "we don't believe there's much of a link between El Niño and climate change," he says.

Willoughby and Kirtman agree. Even if climate change is playing some unknown role, it would be adding only a small percentage to the chances of a storm like Patricia forming. A single record-breaking event, even within in a record El Niño year, cannot be linked to climate change.

"Maybe we'll look back in a hundred years and say, 'this is where it all began,'" says Willoughby. But even if that doesn't happen, he predicts global warming will eventually heat the oceans to the point that this kind of rapidly intensified hurricane becomes more frequent.

"We can look at what's going on right now and say it's a preview of what a warmer globe is likely to be," he says.

Copyright 2015 NPR. To see more, visit http://www.npr.org/.

Transcript

ARI SHAPIRO, HOST:

We continue to watch Hurricane Patricia as it reaches the west coast of Mexico. With peak winds over 200 miles an hour, Patricia is the most powerful storm ever recorded in the Western Hemisphere. It grew to be that way very quickly. NPR's Geoff Brumfiel has the story of how Patricia became a monster.

GEOFF BRUMFIEL, BYLINE: On Thursday morning, Patricia was a relatively small category 1 hurricane. By Friday afternoon, it was a category 5.

BEN KIRTMAN: It's a little bit like a perfect storm; lots of the things come together in order to produce a rapid intensification.

BRUMFIEL: Ben Kirtman is with the University of Miami. Researchers aren't great at predicting when storms will strengthen quickly.

KIRTMAN: This is one of the toughest things for us to do.

BRUMFIEL: But they do know a lot about why it happens. Hugh Willoughby with Florida International University says most hurricanes develop under imperfect conditions that slow their growth and can eventually stop them altogether. Patricia is different.

HUGH WILLOUGHBY: In a storm like this, everything is right, and that's what they do if they're not interfered with. That's my take on it.

BRUMFIEL: One key source of fuel for Patricia was warm water. The Eastern Pacific has been very warm this year, thanks to a near-record ocean-warming phenomenon known as El Nino. Going one step farther, one might wonder whether climate change caused the record El Nino which caused this record-breaking hurricane. Willoughby says that's impossible to prove, in part because the link between climate change and El Nino is not understood. It's just too soon to tell.

WILLOUGHBY: Maybe we'll look back in 100 years and say, this is where it all began. But even if we don't, we can look at what's going on now and say, it's a preview of what a warmer globe is likely to be.

BRUMFIEL: Researchers predict oceans will warm in coming decades and that will mean more fast-growing, strong hurricanes in our future. Geoff Brumfiel, NPR News. Transcript provided by NPR, Copyright NPR.