Key climate change indicators hit record highs in 2021: UN report

Greenhouse gas concentrations, sea level rise, ocean heat and ocean acidification all set new records last year.

A formerly sunken boat rests on a now-dry section of lakebed at the drought-stricken Lake Mead, Nevada
A formerly sunken boat rests on a now-dry section of lakebed at the drought-stricken Lake Mead, Nevada [File: Mario Tama/Getty Images]

Four key climate change indicators all set new record highs in 2021, the United Nations has said, warning that the global energy system was driving humanity towards catastrophe and calling for an urgent transition to renewable energy.

Greenhouse gas concentrations, sea level rise, ocean heat and ocean acidification all set new records last year, the UN’s World Meteorological Organization (WMO) said in its State of the Global Climate in 2021 report released on Wednesday.

“Our climate is changing before our eyes,” said WMO chief Petteri Taalas.

“The heat trapped by human-induced greenhouse gases will warm the planet for many generations to come. Sea level rise, ocean heat and acidification will continue for hundreds of years unless means to remove carbon from the atmosphere are invented.”

The levels of climate-warming carbon dioxide and methane in the atmosphere in 2021 surpassed previous records, the WMO said.

The report also confirmed that the past seven years were the top seven hottest years on record.

Globally, the average temperature last year was 1.11 degrees Celsius above the preindustrial average, as the world inches closer to the 1.5 C threshold beyond which the effects of warming are expected to become drastic.

Last year’s temperatures were tempered slightly compared with 2020 because of the cooling effects of La Nina in the Pacific.

“It is just a matter of time before we see another warmest year on record,” Taalas said.

The world’s oceans have warmed markedly faster in the last 20 years, hitting a new high in 2021, the report said. That change would likely take centuries or millennia to reverse, it noted.

Oceans bear much of the brunt of the warming and emissions, absorbing about 90 percent of the Earth’s accumulated heat and 23 percent of the carbon dioxide emissions from human activity.

Ocean acidity is now at its highest in at least 26,000 years as the water absorbs and reacts with more carbon dioxide in the atmosphere.

Moreover, sea levels have risen 4.5cm (1.8 inches) in the last decade, with the annual increase from 2013 to 2021 more than double what it was from 1993 to 2002.

The WMO report said rising global temperatures had contributed to many extreme events across the globe.

“Lytton, British Columbia reached 49.5 degree Celsius, breaking the previous Canadian record by 4.6 degrees,” Blair Trewin, one of the authors of the report said.

“Extreme heat was not the only story. Extreme cold hit southcentral America in February in the most costly winter storm on record,” he said while adding that Madrid, Spain had its highest recorded snowfall since 1971.

UN’s renewables plan

UN chief Antonio Guterres said the annual overview is “a dismal litany of humanity’s failure to tackle climate disruption” and that the “global energy system is broken and bringing us ever closer to climate catastrophe”.

“We must end fossil fuel pollution and accelerate the renewable energy transition before we incinerate our only home,” he added.

Guterres outlined a five-point global plan to speed up the use renewable energy rather than coal, gas and oil.

As part of the plan, Guterres called for fostering technology transfer and lifting of intellectual property protections in renewable technologies, like battery storage. He also highlighted the need to broaden access to supply chains and raw materials that go into renewable technologies, which are now concentrated in a few powerful countries.

Cutting fuel subsidies was also necessary, while private and public investments in renewable energy must triple to at least $4 trillion dollars a year, the UN chief noted.

Moreover, Guterres said it was important for world governments to enacts reforms to fast track solar and wind projects.

“If we act together, the renewable energy transformation can be the peace project of the 21st century,” he said.

Source: Al Jazeera and news agencies