Forecasters fear ‘supercharged’ Atlantic hurricane season due to ‘recurrent currents’ in Gulf of Mexico | Science & Technology News
Forecasters are predicting a particularly busy Atlantic hurricane season and fear that conditions are ripe to increase pressure for some devastating storms.
Two of the most damaging hurricanes in history, Category four Opal in 1995 and Category five hurricane Katrina in 2005, were enhanced by something called the Ring Current in the Gulf of Mexico.
This current protrudes through the Yucatan Channel into the belly of the bay before exiting through the Florida Strait. This year, it pushed much further north than usual.
The US National Oceanic and Atmospheric Administration (NOAA) explains: “As the Loop Current is prolonged, it eventually releases a large eddy, or Vortex, which then drifts westward, while the Loop Current withdraws to the South”.
A tornado from Hurricane Katrine powered by Loop Current rose from a tropical storm as it passed through the Florida Straits into a category five hurricane, which eventually flooded much of New Orleans and caused damage. damage more than 100 billion USD.
For the seventh year in a row NOAA has forecast an above-average hurricane season, with 14 to 21 named storms, with 70% confidence.
Meteorologists fear that if one of these tropical storms passes through the deep warm waters of the Current, they could strengthen into powerful storms – and happen almost overnight.
NOAA expects three to six major hurricanes – above Category three with winds of 111 mph or more.
Writing for The Conversation, Professor Nick Shay at the University of Miami said: “I’ve been monitoring ocean temperatures for over 30 years as a marine scientist. The conditions I saw in the Gulf in October 5 2022 is worrisome.”
He described Cyclone as “the 800-pound gorilla of Gulf storm risk” and said: “When Cyclone reaches this north pole at the start of the hurricane season – especially during what is forecast to be a storm busy season – it could spell disaster for people along the North Gulf Coast, from Texas to Florida.”
Storm ‘exploded almost overnight’
Prof Shay said the Ring Current helped Cyclone Ida in August 2021 “explode almost overnight” as its surface temperatures above 30 degrees Celsius (86F) extended down to about 180m (590ft).
This year, in mid-May, Ring Stream had water temperatures of around 25 degrees Celsius (78 F) up to 100m (330ft) deep and Prof Shay said he expected this to develop.
“During a storm, warm ocean water can create incredibly high plumes of warm, humid air, providing high-octane fuel for hurricanes,” he explains.
“As more humidity and heat build up in the storm, the pressure drops. The horizontal pressure difference from the center of the storm to its periphery then causes the winds to accelerate and the storm to become increasingly more intense. hazardous.”
Because Loop Current’s water is “deeper and warmer, and also saltier than typical water in the Gulf,” it can trap heat at great depths, providing storms with a powerful source of energy.
‘Get ready now’
The strongest and most damaging storms on record occurred late in the season, in August and September, when summer continued to contribute to weather effects.
“It’s important that people understand their risks and take proactive steps to get ready now,” warned Deanne Criswell, administrator of the US Federal Emergency Management Agency.
How do they make these predictions?
There are a number of climatic factors contributing to this season, including La Nina, higher sea surface temperatures in the Atlantic and Caribbean, and a bountiful West African monsoon season.
La Nina is expected to reduce absolute winds – changes in wind speed and direction – which could help calm a sudden storm by weakening and destabilizing it.
African weather leads to much stronger resurrection waves, which is how many of the strongest and longest-lasting Atlantic hurricanes begin to form.
“Preparing early and understanding your risks is key to being hurricane resilient and climate ready,” said US Commerce Secretary Gina Raimondo.
“During hurricane season, NOAA experts will work around the clock to provide accurate and early forecasts and warnings that communities in the storm’s path can depend on to survive,” Ms. Raimondo added. updated.