The world’s oceans have never been warmer, with the average measured temperature reaching 21.1 degrees Celsius

The world’s oceans have never been warmer than they were last weekend. According to the EU’s Copernicus program, the average measured temperature was 21.1 degrees Celsius. CO₂ emissions and El Niño are the main causes.

On August 22, the world’s oceans were warmer than ever before since measurements began in 1979. According to data from the EU’s Copernicus program, the global average surface temperature of the seas and oceans reached 21.1 degrees Celsius.

Climate researchers were particularly surprised by the timing of this record. Sea and ocean temperatures around the world are usually highest in March and April, after summer in the Southern Hemisphere. The previous record of 21.09 degrees was recorded in March 2024.

The new record comes after a series of monthly records and near-record figures recorded during this year.

CO₂ emissions and El Niño as the main causes

According to Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research, the new record is primarily a consequence of global warming caused by greenhouse gas emissions, particularly from the burning of oil, natural gas and coal.

Temperatures are also rising further because of the El Niño climate phenomenon in the Pacific Ocean, which occurs every few years and causes particularly high temperatures in the tropical regions there, explained Samantha Burgess, strategic climate lead at Copernicus.

The new temperature record is another sign that the oceans are coming under increasing pressure. As temperatures in the seas and oceans rise, the risks to residents of coastal areas and ecosystems also increase.

According to Rahmstorf, one consequence is the destruction of coral reefs around the world, which is considered a climate tipping point. Science has been warning of this risk for years.

The risk of heavy rainfall and storms is increasing

According to Copernicus, higher sea temperatures also increase the risk of extreme weather events. A warmer ocean releases more heat and moisture into the atmosphere, which can cause heavier rainfall and more powerful storms. It may also absorb CO₂ from the atmosphere less efficiently, thereby weakening one of the most important natural protective mechanisms against climate change./DW