A new analysis by the European Union’s Copernicus Climate Change Service, which tracks global temperature and other climate indicators, found 2021 was the fifth-warmest year on record.
“The really important thing is to not get hung up on the ranking of one particular year but rather kind of see the bigger picture of ever-warming temperatures, and that ever-warming doesn’t mean every year will be warmer than the next,” said Freja Vamborg, senior scientist at Copernicus. “But that was what we’ve seen so far with every decade warmer than the next — and this is quite likely to continue.”
Earth’s average temperature is around 1.1 degrees Celsius above average pre-industrial levels, Copernicus reports, 73% of the way to the 1.5-degree threshold scientists warn the planet must stay under to avoid the worst impacts.
Kim Cobb, director of the Global Change Program at the Georgia Institute of Technology, said a warming of 1.1 degrees Celsius is a “conservative” estimate.
“It is very fair to say that 1.1 degrees Celsius is conservative, because the last half of the last decade has been warmer than the first half,” Cobb, who is not involved with the report, told CNN.
1.1 Celsius
In 2015, world leaders agreed to heed scientists’ warnings and limit Earth’s rapid temperature rise to below 2 degrees Celsius above pre-industrial levels, with a preferred goal of 1.5 degrees.
For the planet, scientists are tracking Earth’s temperature increase from the baseline at the start of the Industrial Revolution in the mid-to-late 19th century, when humans ramped up the burning of fossil fuels like coal and oil.
Cobb said for every increment of future warming, the latest climate research outlines cascading consequences that would threaten every aspect and necessity on Earth including biodiversity, freshwater, and food supplies.
“We’ve just barely crossed the 1 degree threshold for warming, and yet we are reeling from a near-constant series of weather and climate extremes,” Cobb told CNN. “With rare exceptions, these extremes can now be definitively linked to human-caused warming. Going forward, we should expect the frequency and severity of such extremes to increase, exacting an enormous toll on societies around the world.”
‘Inspiring’ reason for hope
Experts warned global greenhouse gas emissions in 2030 will still be roughly twice as high as what’s necessary to limit warming to 1.5 degrees. Even worse, under current policies — not proposals, but rather what countries are actually doing right now — the climate tracker projects global temperatures to climb a catastrophic 2.7 degrees Celsius.
At that point, the planet would be in critical condition. The Copernicus report showed carbon emissions continued a precipitous trend in 2021, despite a global pandemic. Emissions from methane, a greenhouse gas roughly 80 times more potent than carbon dioxide in the short-term, continued to rise “very substantially.”
Vamborg highlighted the report serves as a reminder the rise in greenhouse gas emissions is what fuels the planet’s rapid warming, adding the “global temperature curve will continue going up as we continue emitting greenhouse gases.”
“The idea that we might live to see a reversal of global warming is inspiring, as generations that have witnessed decade after decade of warming,” Cobb said. “It’s a future worth fighting for, and bringing to life, one energy choice at a time.”