The effects of Hurricane Melissa They are already being noticed in Jamaica, with torrential rains and strong winds. Its intensity is reminiscent of that of Milton, the hurricane that affected the Yucatan Peninsula and Florida last year.
Both cases are a clear example of how the increase in the average temperature of the ocean surface causes these weather phenomena to become more and more extreme. This is what experts have been warning about for years.
Melissa has already reached a maximum sustained wind intensity of 289 km/h, making it the the fifth most intense hurricane that has ever been recorded in the Atlantic.
It may still be early to correlate it with warming of the oceansbut what catches scientists’ attention is that it is the fourth tropical storm in the Atlantic to undergo rapid intensification, both in its speed and power, this year.
Double the odds
This intensification has already been related to the climate crisis that human activity is causing. As in the Mediterranean, in the Atlantic area affected by this hurricane there are values between 2 and 3 ºC above normal.
These unusually warm temperatures are also occurring in the deepest layers of the ocean, so provides a huge energy reserve for what was the tropical torment Melissa.
In 2024, the global mean ocean surface temperature will reach a historical record of 21 °Csurpassing all previous records. The Climate Central organization estimates that Melissa has intensified up to 700 times more than would be likely due to climate change.
One of its managers has declared a Associated Press This does not mean that all tropical storms will have rapid intensification. However, since “the energy it provides is enormous,” the probability of its occurrence is greater.
Some recent research suggest that warmer sea surface temperatures may contribute to a greater proportion of tropical cyclones (including hurricanes and tropical storms) undergoing rapid intensification.
Precisely a studypublished in 2023, warned that Atlantic hurricanes are now more than twice as likely as before to rapidly intensify and go from minor storms to powerful and catastrophic phenomena.
And since 1979 the warming caused by human activity has increased the global probability of a tropical cyclone becoming a major hurricane by about 5% per decade.
In addition to climate change, this extreme warming is also associated with phenomena such as ‘El Niño’, since they involve alterations in atmospheric and oceanic circulation, with thermal anomalies that can exceed 3 ºC with respect to normal values.
Close to the coast
The intensification of hurricanes due to the warming of the oceans is becoming more noticeable at points near the coast, as they are usually the last areas where these phenomena absorb energy before making landfall.
The United States National Oceanic and Atmospheric Administration (NOAA) already predicted that the Atlantic hurricane season was going to be more active than usual this year, with between two and five hurricanes of great intensity.
The prediction, for the moment, is being quite accurate. And of the five hurricanes that have formed to date, not counting Melissa, three of them have reached great intensity (Erin, Gabrielle and Humberto).
The intensity of these hurricanes may not have been as high without climate change. a report Climate Central, in fact, showed that Beryl and Milton They would not have become Category 5 hurricanes without the influence of climate change.
Hurricane Milton rapidly intensified by 193 km/h in less than 36 hours over waters whose warming became 400 to 800 times more likely due to climate change. In Beryl, climate change made warm ocean waters up to 400 times more likely.
another study of this organization analyzed the more than 30 hurricanes that occurred in the Atlantic between 2019 and 2023. Climate change also increased the intensity of most of them.
In about thirty of them, intensities one category higher on the Saffir-Simpson hurricane wind scale were reached. The potential wind damage associated with each category increases four-fold with each jump, as explains the meteorologist Francisco Martín León.
Climate change also caused the maximum wind speeds generated by approximately 80% of hurricanes intensified in an average of 29 km/h.
It is estimated that just a 1°C increase in ocean surface temperature can increase hurricane wind speeds by up to 5%.