The “800 pound gorilla” in the Gulf of Mexico that could supercharge hurricanes this season

The “800 pound gorilla” in the Gulf of Mexico that could supercharge hurricanes this season

Forecasters expect a busy 2022 Atlantic hurricane season, with a 65 percent chance of an above-average season. There’s also a wildcard in the mix that raises the risk of more severe storms in the Gulf of Mexico this year.

Between 14 to 21 tropical storms could grow powerful enough to be named this season, the National Oceanic and Atmospheric Administration (NOAA) said in its season outlook briefing, which was released today. The average Atlantic hurricane season, which starts on June 1st, typically has about 14 named storms. Another prominent forecast from Colorado State University predicted 19 named storms this year.

NOAA expects six to 10 storms to strengthen into hurricanes. NOAA also forecast between three to six major hurricanes, ranked as a Category 3 or higher with wind speeds of at least 111 miles per hour.

There’s also a troubling development in the Gulf of Mexico. The Loop Current, a current of warm water, has moved surprisingly far north for this time of year. The current, which flows like a river within the sea, brings warmer water from the Caribbean to typically cooler waters closer to the US Gulf Coast. That’s especially worrying news for the season since hurricanes feed off heat energy.

“It’s higher octane fuel,” says University of Miami oceanography professor Nick Shay. “It’s the 800 pound gorilla in the Gulf.”

Shay is concerned that the Loop Current’s current behavior looks similar to the 2005 Atlantic Hurricane season — when hurricanes Katrina, Rita, and Wilma ripped through Gulf Coast communities.

“In 2005, we have what is known as the hurricane Trifecta in the Gulf of Mexico,” Shay says. Both Katrina and Rita developed explosively into Category 5 storms after crossing paths with the Loop Current’s warmer waters. Hurricanes Ida in 2021 and Harvey in 2017 were also strengthened by the Loop Current.

The Loop Current’s water is also saltier. Differences in temperature and salinity between the Loop Current and the rest of the Gulf limit ocean water mixing, which might normally bring surface temperatures down.

As a result, the current holds onto heat at much deeper depths than the surrounding Gulf. Water temperatures of 78 degrees Fahrenheit in the current can reach up to 500 feet below the surface. Outside of the current, those kinds of temperatures usually only reach 100 feet below the surface. “It’s a big difference,” Shay says.

But Shay cautions that it’s too soon to tell whether something similar to 2005 could happen this season. It will depend on whether any storms move toward the Loop Current (or toward large circling pools of hot water that spin off from the current, called eddies). Whether the Loop Current can successfully supercharge storms will also depend on whether storms form during favorable atmospheric conditions and low wind shear.

Strong wind sheer, changes in the wind’s speed and direction, can destabilize or weaken a storm. But a weather pattern called La Niña is expected to keep wind shear low throughout the hurricane season, a factor that could up the chances of stronger storms developing.

NOAA also pointed to an “enhanced” west African monsoon affecting this year’s Atlantic season. The west African monsoon, a major wind system, can drive stronger easterly waves that “seed many of the strongest and longest lived hurricanes during most seasons,” NOAA says in its season outlook.

Stronger hurricanes are expected to become more common as climate change heats up the world’s oceans. Warmer than average sea surface temperatures in the Atlantic Ocean and Caribbean Sea are also likely to boost hurricane activity this season, NOAA said today.

There’s also evidence that hurricanes have begun to intensify more quickly and keep their strength for longer after making landfall as global average temperatures rise. The Loop Current’s warm eddies also seem to hold more heat than they have in the past, Shay says, although scientists can’t yet pinpoint why.

Should NOAA’s predictions for 2022 come true, it would be the seventh consecutive above-normal season for the Atlantic.

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