In the middle of a historically sweltering summer, a NASA researcher stood before Congress and declared the unvarnished, undeniable scientific truth: “The greenhouse effect has been detected,” James Hansen said. “And it is changing our climate now.”
The year was 1988. Global temperatures were about 0.6 degrees Celsius (1.1 degrees Fahrenheit) above the preindustrial average. It was, at the time, the hottest 12-month period scientists had ever seen.
None of us will ever experience a year that cool again.
1.5ºC above 1880-1899 average
6ºF above 1880-1899
+1.1ºC
average
1
Global temperatures in 2021 averaged 1.1ºC above the late 1800s
3
0.5
0
0
Five-year average
−3
1880
1900
1950
1980
2020
Source: NASA
In 2021, global temperatures were between 1.1 and 1.2 degrees Celsius (2.2 degrees Fahrenheit) above the preindustrial average, according to new data from NASA, the National Oceanic and Atmospheric Administration and Berkeley Earth.
Despite a La Niña weather pattern in the Pacific Ocean, which tends to cool the planet, 2021 was roughly tied for sixth-hottest year ever observed, scientists say. All of the seven hottest years on record have happened in the last seven years.
The new global temperature data sets, which come from three of the world’s top climate research institutions, are packed with alarming signs of a world in crisis. More than two dozen countries that are home to about 1.8 billion people experienced their warmest years ever last year. July was the hottest month humanity has recorded. The heat dome that seared the Pacific Northwest this past summer was “the most anomalous extreme heat event ever observed on Earth,” in the words of one scientist — a disaster so severe that it would have been virtually impossible in a world without climate change.
Residents at a cooling center on June 28, 2021, during a heat wave in Portland, Ore. (Maranie Staab/Bloomberg)
Overall, last year did not smash as many global records — it ranked seventh lowest for Northern Hemisphere snow cover, ninth smallest for average Arctic sea ice extent and 10th highest for number of named tropical storms, depending on the data set consulted.
Sinkholes, landslides, collapsing roads: 70 percent of Arctic infrastructure at risk from permafrost melt, scientists say
But the fact that 2021 didn’t rewrite the history books makes it even more sobering, said NASA climatologist Gavin Schmidt. It underscores the extent to which human greenhouse gas emissions, primarily from burning fossil fuels, have fundamentally and irrevocably changed the planet. Even the not-quite-so-bad years are dramatically worse than anything that could have been imagined a generation ago. Natural variation, like the cooling influence of La Niña, can barely put a dent in the relentless man-made warming trend.
The year 2021 was the seventh in a row in which global temperatures were more than 1 degree Celsius above the preindustrial average. It’s unlikely anyone alive will see the world’s temperature drop below that 1-degree benchmark again.
“There is no going back,” said Schmidt, director of the NASA Goddard Institute for Space Studies and a lead researcher on the agency’s annual temperature analysis. The roughly 1.5 trillion tons of carbon dioxide emitted by humans — more than half of it in the 34 years since Hansen’s testimony — will not leave the atmosphere for at least several more centuries.
Schmidt added: “We are reaping what we’ve sown.”
More than 40 percent of Americans live in counties hit by climate disasters in 2021
The three climate reports released Thursday, along with a fourth analysis from the European Union’s Copernicus Climate Change Service published Monday, differ slightly because they draw on different data sets. The European group ranked 2021 as the fifth-hottest year on record, just ahead of 2015 and 2018. NASA has the year tied for sixth with 2018, while Berkeley Earth researchers said it could fall anywhere between fifth and seventh.
“What really matters for the climate isn’t exactly where 2021 falls, it’s that it continues the extremely clear trend of very high temperatures,” said Zeke Hausfather, a climate scientist at the Breakthrough Institute and Berkeley Earth.
A truck sprays water to cool a hot street as people holding umbrellas line up for coronavirus testing in Seoul on July 26, 2021. (Ahn Young-joon/AP)
Since 1981, average global temperatures have increased at a rate of about 0.18 degrees Celsius (0.32 degrees Fahrenheit) per decade. In the same period, the warming of oceans — which have absorbed about 90 percent of the additional heat trapped by human carbon pollution — has gotten eight times faster. According to a new analysis published Tuesday in the journal Advances in Atmospheric Sciences, the oceans now contain more energy than at any point since record-keeping began.
The year was 1988. Global temperatures were about 0.6 degrees Celsius (1.1 degrees Fahrenheit) above the preindustrial average. It was, at the time, the hottest 12-month period scientists had ever seen.
None of us will ever experience a year that cool again.
1.5ºC above 1880-1899 average
6ºF above 1880-1899
+1.1ºC
average
1
Global temperatures in 2021 averaged 1.1ºC above the late 1800s
3
0.5
0
0
Five-year average
−3
1880
1900
1950
1980
2020
Source: NASA
In 2021, global temperatures were between 1.1 and 1.2 degrees Celsius (2.2 degrees Fahrenheit) above the preindustrial average, according to new data from NASA, the National Oceanic and Atmospheric Administration and Berkeley Earth.
Despite a La Niña weather pattern in the Pacific Ocean, which tends to cool the planet, 2021 was roughly tied for sixth-hottest year ever observed, scientists say. All of the seven hottest years on record have happened in the last seven years.
The new global temperature data sets, which come from three of the world’s top climate research institutions, are packed with alarming signs of a world in crisis. More than two dozen countries that are home to about 1.8 billion people experienced their warmest years ever last year. July was the hottest month humanity has recorded. The heat dome that seared the Pacific Northwest this past summer was “the most anomalous extreme heat event ever observed on Earth,” in the words of one scientist — a disaster so severe that it would have been virtually impossible in a world without climate change.
Residents at a cooling center on June 28, 2021, during a heat wave in Portland, Ore. (Maranie Staab/Bloomberg)
Overall, last year did not smash as many global records — it ranked seventh lowest for Northern Hemisphere snow cover, ninth smallest for average Arctic sea ice extent and 10th highest for number of named tropical storms, depending on the data set consulted.
Sinkholes, landslides, collapsing roads: 70 percent of Arctic infrastructure at risk from permafrost melt, scientists say
But the fact that 2021 didn’t rewrite the history books makes it even more sobering, said NASA climatologist Gavin Schmidt. It underscores the extent to which human greenhouse gas emissions, primarily from burning fossil fuels, have fundamentally and irrevocably changed the planet. Even the not-quite-so-bad years are dramatically worse than anything that could have been imagined a generation ago. Natural variation, like the cooling influence of La Niña, can barely put a dent in the relentless man-made warming trend.
The year 2021 was the seventh in a row in which global temperatures were more than 1 degree Celsius above the preindustrial average. It’s unlikely anyone alive will see the world’s temperature drop below that 1-degree benchmark again.
“There is no going back,” said Schmidt, director of the NASA Goddard Institute for Space Studies and a lead researcher on the agency’s annual temperature analysis. The roughly 1.5 trillion tons of carbon dioxide emitted by humans — more than half of it in the 34 years since Hansen’s testimony — will not leave the atmosphere for at least several more centuries.
Schmidt added: “We are reaping what we’ve sown.”
More than 40 percent of Americans live in counties hit by climate disasters in 2021
The three climate reports released Thursday, along with a fourth analysis from the European Union’s Copernicus Climate Change Service published Monday, differ slightly because they draw on different data sets. The European group ranked 2021 as the fifth-hottest year on record, just ahead of 2015 and 2018. NASA has the year tied for sixth with 2018, while Berkeley Earth researchers said it could fall anywhere between fifth and seventh.
“What really matters for the climate isn’t exactly where 2021 falls, it’s that it continues the extremely clear trend of very high temperatures,” said Zeke Hausfather, a climate scientist at the Breakthrough Institute and Berkeley Earth.
A truck sprays water to cool a hot street as people holding umbrellas line up for coronavirus testing in Seoul on July 26, 2021. (Ahn Young-joon/AP)
Since 1981, average global temperatures have increased at a rate of about 0.18 degrees Celsius (0.32 degrees Fahrenheit) per decade. In the same period, the warming of oceans — which have absorbed about 90 percent of the additional heat trapped by human carbon pollution — has gotten eight times faster. According to a new analysis published Tuesday in the journal Advances in Atmospheric Sciences, the oceans now contain more energy than at any point since record-keeping began.
