Earth’s oceans are hotter than ever with accumulated heat in the upper ocean at record levels, breaking the temperature record for a sixth consecutive year
Published in the Advances in Atmospheric Sciences journal, the report summarises two international datasets: from the Institute of Atmospheric Physics (IAP) and from the National Centres for Environmental Information of the National Oceanic and Atmospheric Administration (NOAA), that analyse observations of ocean heat content and their impact dating from the 1950s.
“Ocean heat content is relentlessly increasing, globally, and this is a primary indicator of human-induced climate change,” said author Kevin Trenberth, the National Center for Atmospheric Research in Colorado.
“In this most recent report, we updated observations of the ocean through 2021, while also revisiting and reprocessing earlier data.”
Ocean heat content is relentlessly increasing, globally
This is a primary indicator of human-induced climate change.
Researchers found that the upper 2,000 meters in all oceans absorbed 14 more Zettajoules than in 2020, equal to 145 times world electricity generation in 2020. For context, all the energy humans use over the world in single year is about half of a Zettajoule.
The oceans absorbs 20 to 30% of human carbon dioxide emissions, leading to ocean acidification however according to the papers lead author Lijing Cheng ‘ocean warming reduces the efficiency of oceanic carbon uptake and leaves more carbon dioxide in the air.”
“Monitoring and understanding the heat and carbon coupling in the future are important to track climate change mitigation goals” says Cheng.
The danger of rising ocean temperatures
Regional analyses show that the robust and significant ocean warming since the late 1950s occurs everywhere according to Cheng and regional marine heat waves are a consequence, with huge impacts on marine life.
“Our previous work showed that scientists need less than 4 years of ocean heat measurements to detect a human-induced warming signal from natural variations. This is much shorter than the nearly three decades of measurements required to detect global warming using temperatures of air near the Earth’s surface,” said John Abraham, Professor of University of St. Thomas.
This report shows that human activity directly affects ocean warming and therefore the percentage of ice and the rising sea levels around the globe.
“Warmer oceans also supercharge weather systems, creating more powerful storms and hurricanes, as well as increasing precipitation and flood risk,” said Cheng. “Better awareness and understanding of the oceans are a basis for the actions to combat climate change.”
However, these changes need to be made quickly and efficiently in order to protect out oceans and world as we know it.