Hurricane Lee crosses the Atlantic Ocean as it moves west on September 8, 2023. Ocean heat is fueling stronger hurricanes. —
Global average ocean temperatures in 2023 were 0.25 degrees Celsius warmer than the previous year, said Gregory C. Johnson, a NOAA oceanographer. That rise is “is equivalent to about two decades’ worth of warming in a single year,” he told CNN. “So it is quite large, quite significant, and a bit surprising.”
High ocean temperatures are already proving catastrophic for coral. Australia’s Great Barrier Reef is experiencing its seventh mass bleaching event, authorities announced in March following aerial surveys. Ocean heat sets the stage for more ferocious hurricanes. “The warmer the ocean, the more energy to fuel storms is available,” said Karina von Schuckmann, an oceanographer at Mercator Ocean International in France.
If very high ocean temperatures continue into the second half of 2024 and a La Niña event develops — El Niño’s counterpart that tends to amplify Atlantic hurricane season — “this would increase the risk of a very active hurricane season,” Hirschi said.