The world's oceans are suffering from a record year of heat

2024-05-08 09:30:00, Kosova & Bota CNA

Fueled by climate change, the world's oceans have broken temperature records every day over the past year.

According to an analysis by the BBC, gases that warm the planet are responsible, but El Niño has also affected the warming of the seas.

Super-hot oceans have hit marine life hard and fueled a new wave of coral bleaching.

Copernicus also confirmed that last month was the warmest April in terms of air temperatures, extending that streak of month-specific records.

For decades, the world's oceans have been Earth's "get out of jail" when it comes to climate change.

They not only absorb about a quarter of the carbon dioxide that humans produce, but also absorb about 90% of excess heat.

But over the past year, the oceans have shown the most worrying evidence yet that they are struggling to cope, with the sea surface particularly feeling the heat.

From March 2023, the average surface temperature of the global oceans began to move increasingly above the long-term norm, reaching a new record in August.

Recent months have brought no respite, with sea levels reaching a new global average of 21.09 degrees Celsius in February and March this year, according to Copernicus data.

As the chart below shows, not only has every day since May 4, 2023 broken the daily record for the time of year, but on some days the gap has been wide. Some 47 days broke the record for that day of the year by at least 0.3 degrees Celsius, according to the BBC's analysis of Copernicus data.

Never before in the satellite era has the record margin been so wide.

The biggest record-breaking days were August 23, 2023, January 3, 2024, and January 5, 2024, when the previous temperature was beaten by about 0.34 degrees Celsius.

Major impact on marine life

According to a recent study, this human-driven ocean warming is having significant impacts on global marine life and may even be shifting the seasonal cycle of sea temperatures.

Perhaps the most significant consequence of recent warming has been the massive bleaching of corals globally.

These major ocean "nurseries" turn white and die because the waters they live in get too hot. They are a critical element in the ocean ecosystem, home to about a quarter of all marine species.

In the UK, rising sea temperatures are having an impact, with a number of creatures having completely disappeared from coastal sites - for example, some species of barnacles.

The El Niño effect

An important factor that has made last year more impactful on seas around the world has been the El Niño weather phenomenon, adding to human-caused greenhouse gas emissions.

El Niño began in June 2023, after an extended period of cooler La Niña conditions, and peaked in December, although it has since faded./ CNA