NASA research supports climate change theory
The claim: NASA ‘admits’ polar ice has increased since 1979 and denies significant warming over the past 18 years
However, a meme began circulating again in late 2021, saying “NASA now admits that polar ice has increased beyond its 1979 volume and there has been no significant warming in 18 years.”
An example of the meme, originally posted on Facebook in October 2020 and circulating again last month, garnered hundreds of shares.
USA TODAY has found no evidence that NASA made the claimed statements. NASA data shows that Arctic sea ice and ice caps at both poles have been steadily shedding ice for decades and warming has continued for the past 18 years. Antarctic sea ice has not shown a strong global trend of gain or loss since 1979.
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USA TODAY has reached out to Facebook and Twitter users as well as a blogger who shared the meme for comment. Reddit user could not be reached.
NASA says there has been significant warming over the past 18 years
NASA spokeswoman Tylar Greene told USA TODAY in an email that she was not aware of any official statement the meme might refer to.
“Human-caused warming has continued over the past 18 years, which is evident not only in surface instrumental records, but also in satellite temperature records, melting glaciers, sea level rise, increases ocean heat content, and a number of other signs of a warming world,” Greene said.
NASA’s global temperature data is publicly available on the organization’s website. Website Vital Signs of the Planet.
“Nineteen of the warmest years (on record) have occurred since 2000, with the exception of 1998, which was aided by a very strong El Niño,” depending on the website.
Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, also told USA TODAY that significant warning trends have continued over the past 18 years.
“The years 2016 and 2020 tied for the hottest year on record,” he said in an email.
NASA announces significant loss of polar ice since 1979
The meme claims that the volume of polar ice has increased beyond its 1979 volume.
NASA does not include complete data on the volume of polar ice on the Vital Signs of the Planet Website. However, other types of data from the site show significant ice loss at Earth’s poles since the late 1970s.
NASA researcher Eric Rignot told USA TODAY that between 1980 and 2019, the Antarctic ice sheet lost nearly 5.4 trillion metric tons of ice. Greenland lost over 5.6 trillion metric tons over the same period.
These estimates are based on a combination of satellite data, physical models, meteorological data and field measurements.
Although NASA ice researchers tend to report these losses in terms of mass, their results can be mathematically converted to volume losses. Volume changes with mass, assuming density is more or less constant.
Schmidt said “there is no doubt” that there has been a significant loss of ice volume from the Greenland and Antarctic ice sheets since 1979.
NASA says Arctic sea ice has shrunk since 1979
The NASA website also indicates that the extent or size of Arctic sea ice has steadily decreased since 1979.
The graph on NASA’s site specifically shows data for “minimum extent,” the time of year when Arctic sea ice reaches its smallest size after the summer melt.
The last time the minimum Arctic sea ice extent approached that of 1979 was in 2001, according to the graph.
Additionally, the average annual extent in 1979 was over 12 million km², while the average annual extent for 2020 was just over 10 million km², according to Claire Parkinson, senior climatologist at NASA.
The annual average extent for 2021 was not yet available.
While there are good satellite records of sea ice extent dating back to 1979, mass and volume estimates are less certain, Parkinson told USA TODAY in an email.
“However, from satellite altimetry data for the past 20 years and underwater and in situ data from before, it is reasonable to conclude that the volume of Arctic sea ice has likely decreased,” she said. .
NASA does not say Antarctic sea ice has increased beyond 1979 levels
While the Arctic sea ice and both ice sheets have lost significant amounts of ice since the late 1970s, the Antarctic sea ice has behaved differently.
“There had been a trend in Antarctica towards an increase in sea ice cover from the late 1970s to 2014, but with the decreases from 2014 to 2017, the record from the late 1970s to now doesn’t show a strong overall trend,” Parkinson said.
Calculations of Antarctic sea ice extent for 2021 are incomplete, but the average annual extent for 2020 was somewhat smaller than in 1979, according to Parkinson.
Even when the Antarctic sea ice reached its peak recorded in 2014, it did not reverse the losses of other ice masses. Global polar ice losses continued.
“The information in this meme is not accurate,” Greene said. “It is contrary to the science that we have published openly and freely on polar ice, global temperatures, and how the planet is changing.”
USA TODAY previously debunked false claims that polar ice has reached record highs in 2021 and the The Greenland ice sheet is gaining ice. In fact, the Arctic sea ice and the ice caps at both poles are in decline.
Our opinion: False
Based on our research, we rate the claim that NASA “admits” that polar ice has increased since 1979 and denies warming over the past 18 years as FALSE. A NASA spokesperson denied any knowledge of such a statement. NASA data shows significant warming over the past 18 years and global polar ice losses since 1979.
Our fact-checking sources:
- USA TODAY, December 21, 2021, Fact check: false claim that Arctic and Antarctic ice has reached record highs
- USA TODAY, December 30, 2021, Fact check: Greenland continues to lose ice; no trend reversal
- NASA, accessed January 19, Ice caps
- NASA, accessed January 19, Extent of arctic sea ice
- NASA, accessed January 19, Climate change: how do we know?
- NASA, accessed January 19, Airplane Vital Signsyou
- NASA, accessed January 19, Global temperature
- Tylar Greene, Dec. 29, 2021-Jan. 7, email exchange with USA TODAY
- Gavin Schmidt, January 6-19, email exchange with USA TODAY
- Claire Parkinson, January 17-18, email exchange with USA TODAY
- Walt Meier, January 18, email exchange with USA TODAY
- Eric Rignot, January 18, email exchange with USA TODAY
- Eric Rignot, January 19, telephone interview with USA TODAY
- NASA, January 14, 2021, 2020 tied for hottest year on record, NASA analysis finds
- NASA, accessed January 7, Sea level
- NASA, accessed January 7, Heat content of the ocean
- Axel Schweiger, January 11-18, email exchange with USA TODAY
- Andrew Berger, January 10-17, email exchange with USA TODAY
- Bonnie Light, January 10-11, email exchange with USA TODAY
- Jinlun Zhang, Email exchange with USA TODAY
- Ian Joughin, January 11-12, email exchange with USA TODAY
- The Washington Post, January 25, 2021, Earth now loses 1.2 trillion tons of ice every year. And it will get worse.
- NASA, accessed January 10, Scientific consensus: Earth’s climate is warming
- Polar Science Center, accessed January 12, PIOMAS reanalysis of Arctic sea ice volume
- The cryosphere, January 25, 2021, Journal Article: Earth’s Ice Imbalance
- PNAS, January 14, 2019, Four decades of Antarctic ice sheet mass balance from 1979 to 2017
- PNAS, April 22, 2019, Forty-six years of Greenland Ice Sheet mass balance from 1972 to 2018
- NASA, February 11, 2015, Despite Antarctic gains, global sea ice is shrinking
- Nature, December 10, 2019, Mass balance of the Greenland ice sheet from 1992 to 2018
- NASA, accessed January 19, GRACE-FO mission
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