Oceans around the world have experienced an entire year of unprecedented heat. A new temperature record is broken every day, new data shows.
Global ocean surface temperatures began breaking daily records in mid-March last year, according to data from the National Oceanic and Atmospheric Administration (NOAA) and the University of Maine's Climate Reanalyzer. The data raises concerns about marine life and extreme weather across the planet.
“In 2023, sea surface temperatures broke records and now we see the same scenario in 2024,” said Joel Hirschi, head of marine systems at the UK's National Oceanography Center.
The global average ocean temperature in 2023 was 0.25°C warmer than the previous year, said Gregory C. Johnson, an oceanographer at NOAA. This increase is “the same as two decades of warming in a single year,” he told CNN . “The result is quite significant and a little surprising.”
Scientists said ocean heat is being overwhelmed by global warming and driven by El Niño, a natural climate phenomenon marked by above-average ocean temperatures.
The main consequences are on marine life and the global climate. Global ocean heat can make hurricanes and other extreme weather events more intense, including scorching heat waves and intense rainfall.
High ocean temperatures are already proving catastrophic for corals. Australia's Great Barrier Reef is experiencing its seventh mass bleaching event, according to local authorities.
Bleaching occurs when heat-stricken corals release the algae that live in their tissues and provide their food source. If ocean temperatures remain too high for too long, coral can starve.
Data from NOAA's Coral Reef Watch shows the problem goes far beyond Australia and that the world could face a fourth global mass coral bleaching event in the coming months.
Heat from the ocean can make hurricanes more intense. “The warmer the ocean, the more energy to fuel storms,” said Karina von Schuckmann, an oceanographer at Mercator Ocean International in France.
Temperatures have been unprecedented in the North Atlantic, a key area for hurricane formation.
“At times, records (in the North Atlantic) have been broken by margins that are statistically impossible,” he told CNN Brian McNoldy, senior research fellow at the University of Miami Rosenstiel School.
If ocean temperatures remain very high until the second half of 2024 and a La Niña event develops – the counterpart to El Niño that tends to amplify the Atlantic hurricane season – “this would increase the risk of a very active hurricane season.” , said Hirschi.
About 90% of the excess heat produced by burning fossil fuels is stored in the oceans. “Measuring ocean warming allows us to track the status and evolution of planetary warming,” Schuckmann told CNN . “The ocean is the sentinel of global warming.”
El Niño is weakening and is forecast to dissipate in the coming months, which could level record ocean temperatures, especially if the cooling effects of La Niña replace it.
“In the past, surface temperature levels have decreased following the passage of El Niño,” Schuckmann said. But he said it is currently impossible to predict when ocean heat will drop below record levels.
While natural climate variability will cause ocean temperatures to fluctuate, over the long term, NOAA's Johnson said, we should expect them to “continue breaking records as long as greenhouse gas concentrations in the atmosphere continue to rise.”
Source: CNN Brasil
Bruce Belcher is a seasoned author with over 5 years of experience in world news. He writes for online news websites and provides in-depth analysis on the world stock market. Bruce is known for his insightful perspectives and commitment to keeping the public informed.
