The indicators are worrying. The oceans broke a new world temperature record this week, raising fears of harmful consequences for marine life and for climate balances. The surface temperature of the oceans “reached 20.96 ° C on July 30” 2023 according to the ERA5 database, while “the previous record was 20.95 ° C in March 2016”, said a spokeswoman. from the European Copernicus service to AFP.
The US Oceanic and Atmospheric Observation Agency (NOAA), which uses a different database, also notes the same warming trend in the oceans in recent months, with a record temperature reached on April 4, at 21.06 degrees. On August 1, the temperature of the oceans was almost at the same level (21.03 ° C) and still above the previous record of 2016.
The oceans absorb 90% of the excess heat from the Earth system caused by human activity during the industrial era and this energy accumulation continues to increase as greenhouse gases accumulate in the atmosphere.
Overheating threatens food security in some regions
“The ocean heat wave poses an immediate threat to some marine life, we are already seeing signs of coral bleaching in Florida as a direct result and I expect further negative consequences,” said Piers Forster, an English professor specializing in climate change.
This overheating of the oceans will have other chain effects on biodiversity, such as the migration of species or the arrival of invasive species threatening fish stocks and therefore food security in certain parts of the globe. In addition, warmer waters have less capacity to absorb CO2 thereby reinforcing the vicious circle of global global warming of the planet.
According to a 2019 IPCC report, sea heat waves have been twice as frequent since 1982. And their intensity could be 10 times greater in 2100 than at the beginning of the 20th century if emissions do not drop.