Earth’s oceans were warmest and most acidic on record in 2021, UN report says

The world’s oceans reached their warmest and most acidic levels on record last year, the World Meteorological Organization (WMO) said on Wednesday, as United Nations officials warned that war in Ukraine threatens commitments global climate issues.

The oceans experienced their most striking extremes when the WMO detailed a series of unrest caused by climate change in its annual report on the state of the world’s climate. He said melting ice caps helped push sea levels to new highs in 2021.

“Our climate is changing before our eyes. Heat trapped by man-made greenhouse gases will warm the planet for many generations to come,” WMO Secretary-General Petteri Taalas said in a statement.

The report follows the latest UN climate assessment, which warned that humanity must drastically reduce its greenhouse gas emissions or face increasingly catastrophic changes in the global climate.

The world’s oceans are the most acidic for at least 26,000 years, the UN agency said. (J. Sumerling/Great Barrier Reef Marine Park Authority via Associated Press)

Taalas told reporters there was little airtime for climate challenges as other crises, such as the COVID-19 pandemic and the war in Ukraine, dominated the headlines.

Selwin Hart, UN Secretary-General Antonio Guterres’ special adviser on climate action, criticized countries for reneging on their climate commitments because of the conflict, which has driven up energy prices and prompted European countries to seek to replace Russia as an energy supplier.

Dangerous increase

“We are seeing … many choices made by many major economies that, quite frankly, have the potential to lock in a high-carbon, high-polluting future and will put our climate goals at risk,” Hart told reporters.

On Tuesday, global stock index giant MSCI warned that the world would face a dangerous rise in greenhouse gases if Russian gas was replaced by coal.

The WMO report says levels of carbon dioxide and methane in the atmosphere in 2021 surpassed previous records.

Globally, last year’s average temperature was 1.11°C above the pre-industrial average, as the world approaches the 1.5°C threshold above which the effects of warming are expected become drastic.

“It’s only a matter of time before we see another hottest year on record,” Taalas said.

The oceans bear much of the brunt of warming and emissions. Bodies of water absorb about 90% of the Earth’s accumulated heat and 23% of carbon dioxide emissions from human activity.

The ocean has warmed significantly faster over the past 20 years, reaching a new high in 2021, and is expected to get even warmer, the report said. This change would likely take centuries or millennia to reverse, he noted.

The ocean is also now its most acidic in at least 26,000 years, as it absorbs and reacts with more carbon dioxide in the atmosphere.

Sea levels have risen by 4.5 centimeters over the past decade, with the annual rise from 2013 to 2021 more than doubling from that from 1993 to 2002.

The WMO has also listed extreme heat waves, wildfires, floods and other climate-related disasters around the world, noting reports of more than $100 billion in damage.