For a year now, the ocean has been setting temperature records every day. And 2024 continues this trend, again breaking previous records by a wide margin over 2023. According to various data sources, the planet as a whole has been experiencing unusually high temperatures for many months.
“There’s no ambiguity about the data,” said Gavin Schmidt, a climate scientist and director of NASA’s Goddard Institute for Space Studies. “So it’s really a matter of attribution.”
Understanding what specific physical processes are behind these temperature records will help scientists improve their climate models and better predict temperatures in the future.
Last month, the global average sea surface temperature reached a new monthly high of 21.07 degrees Celsius, or 69.93 degrees Fahrenheit. This is according to the Copernicus Climate Change Service, a research institution funded by the European Union.
“March 2024 continues a sequence of climate records being shattered for both air temperature and ocean surface temperature,” said Samantha Burgess, deputy director of Copernicus, in a statement this week.
According to a preliminary forecast by scientists at Colorado State University, the tropical Atlantic is abnormally warm, which favors the hurricane season. Higher ocean temperatures provide more energy to strengthen stronger storms.
Global temperatures have been rising for a long time due to greenhouse gas emissions. These gases are produced by burning coal, oil, and other fossil fuels. These gases trap heat in the atmosphere, which leads to an increase in the average global temperature of about 1.2 degrees Celsius or 2.2 degrees Fahrenheit compared to the pre-industrial period. Climate change is already having a major impact, with the oceans absorbing a significant portion of the heat generated by greenhouse gases. This is because it takes more energy to heat water than air.
Concerns of scientists
Але «масові, величезні рекорди», встановлені за останній рік, перевершують те, що очікують But the “massive, huge records” set over the past year exceed what scientists expect to see. Dr. Schmidt even took into account climate change.
“Now, compared to last year, the planet is dealing with the effects of the El Niño phenomenon, which began in July. El Niño events are natural climate patterns associated with rising temperatures.
“The temperatures we’re seeing now, the records broken in February and March, are much more in line with our expectations” compared to last year, Dr. Schmidt said. “We’ll see what happens by summer.”
El Niño is weakening and is expected to dissipate soon. He said what happens to global average temperatures will help shed light on 2023 temperatures.
Aside from climate change and El Niño, several other factors could be contributing to these dizzying records.
One of them is the recent reduction in aerosol pollution from container ships crossing the ocean, which is in line with new international fuel standards that came into effect in 2020. Ironically, aerosols have a cooling impact on the atmosphere and have helped to mask the true extent of climate change until now.
Also, in 2022, the Hunga Tonga-Hunga Ha’apai submarine volcano erupted hugely. Volcanic eruptions that occur on land send out plumes of soot and aerosols that block sunlight and temporarily cool the atmosphere. However, because this volcano was submerged under the Pacific Ocean, its eruption released millions of tons of water vapor into the upper atmosphere. Water vapor is a potent greenhouse gas.
“This was the most explosive eruption since Krakatoa, and it usually takes a year to see the effects,” said Sean Birkel, an associate professor at the University of Maine’s Climate Change Institute who created a climate data visualization tool called the Climate Reanalyzer.
He suspects that the volcanic eruption’s warming effect was greater than previous estimates suggested, noting that the eruption may have affected atmospheric circulation and helped strengthen the El Niño that emerged in 2023. But, he added, more research is needed.
Dr. Schmidt noted that when scientists combined their estimates of how much volcanic eruptions, reduced maritime pollution, El Niño, and climate change should warm the planet, the numbers don’t add up.
“There may be something else missing,” he said, just as other sources of aerosol pollution have improved more than researchers think, or the Earth’s climate has more internal variability than expected, or global warming is amplifying the impact of El Niño.
Several groups of scientists are working to get a clearer picture, Dr. Schmidt said.He expects the results to begin to be published in the next few months.