The four major indicators of climate change all set new record highs in 2021, the United Nations said on Wednesday, warning that the global energy system is pushing humanity toward catastrophe.
Greenhouse gas concentrations, sea level rise, ocean heat and ocean acidification all set new records last year, the UN World Meteorological Organization (WMO) said in its “Global Climate Conditions in 2021” report.
The annual review is “a sad litany of human failure to tackle climate change”, said UN chief Antonio Guterres. “The global energy system is breaking down and bringing us closer to climate catastrophe. We must end fossil fuel pollution and accelerate the transition to renewable energy before we burn down our only homes.”
WMO said human activity is causing planetary scale changes on land, in the oceans and in the atmosphere, with harmful and lasting effects for ecosystems.
Record the heat
The report confirmed that the past seven years were the warmest seven years on record.
Consecutive La Nina events at the beginning and end of 2021 had a cooling effect on global temperatures last year.
Even so, it is still among the warmest years ever on record, with global average temperatures in 2021 about 1.11 degrees Celsius above pre-industrial levels.
The 2015 Paris Agreement on climate change saw countries agree to limit global warming to “well below” 2C above the average level measured between 1850 and 1900 – and 1.5C if possible.
“Our climate is changing before our eyes,” WMO chief Petteri Taalas said.
“The heat trapped by human-caused greenhouse gases will heat the planet for many generations to come. Sea level rise, ocean heat and acidification will continue for hundreds of years unless methods to remove carbon from the atmosphere are invented.”
‘A consistent picture of global warming’
The four key indicators of climate change “build a consistent picture of global warming that is affecting all parts of the Earth’s system”, the report said.
Greenhouse gas concentrations reach new global highs in 2020, when carbon dioxide (CO2) concentrations reach 413.2 parts per million (ppm) worldwide, or 149 percent of pre-industrial levels.
Data shows that it continues to increase in 2021 and early 2022, with the average monthly CO2 in Mona Loa in Hawaii reaching 416.45 ppm in April 2020, 419.05 ppm in April 2021 and 420.23 ppm in April 2022, the report said.
The global average sea level reached a new record high in 2021, rising an average of 4.5 millimeters a year over 2013 to 2021, the report said.
GMSL increased by 2.1 mm per year between 1993 and 2002, with increases between the two time periods “mostly due to accelerated loss of ice mass from ice flakes”, he said.
Signs at sea
Ocean warming hit a record high last year, exceeding 2020 values, the report said.
It is expected that 2,000 meters above the ocean will continue to heat in the future – “an irreversible change on the time scale of a hundred years to the millennium”, the WMO said, adding that the warmth is penetrating to deeper levels.
The oceans absorb about 23 percent of the annual human -induced emissions of CO2 into the atmosphere. While this slows the increase in atmospheric CO2 concentrations, CO2 reacts with seawater and leads to ocean acidification.
The UN Intergovernmental Panel on Climate Change concluded with “very high confidence” that open sea surface acidity was at its highest level “at least 26,000 years ago”.
Meanwhile the report said the Antarctic ozone hole reached an “unusually deep and large” maximum area of 24.8 million square kilometers by 2021, driven by a strong and stable polar vortex.
Guterres proposed five actions to begin the transition to renewable energy “before it’s too late”.
Among them, he proposed ending fossil fuel subsidies, triple investment in renewable energy and making renewable energy technologies, such as battery storage, a global public good available for free.
“If we act together, the transformation of renewable energy could be a 21st century peace project,” Guterres said.
(Except for the headline, this story has not been edited by AGRASMARTCITY staff and is published from a syndicated feed.)