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Fact Check-Comparisons of glacier counts are not a reliable indicator of climate change

Social media users disputing climate change have said there are the same number of glaciers on Earth in 2021 as the day in 1948 that former U.S. vice president Al Gore was born. However, this is a misleading statement, according to three experts who spoke to Reuters, as glaciers tend to split into several smaller glaciers when they melt - and the exact number of glaciers in 1948 is not known.

A meme featuring a photo of Gore (here, here, here), shared tens of thousands of times on Facebook, reads: “The day Al Gore was born there were 130,000 glaciers on Earth. Today, only 130,000 remain.”

Many others shared similar statements, including one Twitter user who suggests there are now 68,000 more glaciers in 2021 (here). Their tweet reads: “The day Al Gore was born there was 130,000 glaciers. Today there are 198,000 glaciers.”

These statements circulated online between late October and early November and coincided with the start of COP26, the United Nations climate change summit.

Reuters has previously addressed instances of misinformation shared in tandem with the Glasgow event, which vary in topic from the talks themselves, to general claims about climate change (here , here , here , here and here).

Firstly, it is problematic to suggest that a comparison between glacier numbers in 2021 and Al Gore’s birth could disprove climate change, three experts told Reuters.

“We don’t know how many glaciers there were in 1948,” Ben Marzeion, a climate scientist and professor at the University of Bremen, said.

That is because there was no satellite imagery at that time, he added. “Since we don’t know how many glaciers there were in 1948, we don’t know whether there are now more or fewer.”

Marzeion directed Reuters to the Randolph Glacier inventory (www.glims.org/RGI/), the first estimate of how many glaciers exist, initially published in 2012.

It now lists around 200,000 glaciers. However, the actual number, according to Marzeion, is likely to be even higher due to issues that include defining a lower limit on the size of what constitutes a glacier.

This, he said, would also make glacier counts an “irrelevant” factor for understanding climate change.

Marzeion told Reuters: “Often a large glacier, when melting, disintegrates into a number of smaller glaciers, thus increasing the number of glaciers.

“Similarly, if you have glaciers growing, their ice streams may join, forming one (but larger) glacier, reducing the number of glaciers.”

Romain Hugonnet, a research assistant and PhD student at the Laboratory of Space Geophysical and Oceanographic Studies (LEGOS), University of Toulouse, said a more accurate climate change indicator would be a measurement of the surface or volume of glaciers.

Peer-reviewed studies show both have been reducing since the 1950s (here and here).

“We know that there was a larger volume of glacier ice in 1948 than today,” Lauren Vargo, a research fellow at Antarctic Research Centre, Victoria University of Wellington, said.

Vargo pointed to a 2015 paper from the World Glacier Monitoring Service (WGMS) (here), which indicated that glacial mass loss rates are "without precedent” according to observations since 1850.

Data from the WGMS, which monitors more than 130 glaciers globally, shows a “global trend in strong ice loss over the past few decades”, with many glaciers disappearing entirely (here).

Further peer-reviewed studies (here, here) and a 2015 World Glacier Monitoring Service paper (here) also indicate dwindling glacier mass over the 20th and 21st centuries.

“We know that glacier loss is largely due to warmer temperatures, which are being driven by increases in greenhouse gases,” Vargo said.

Studies by Marzeion (here) and Vargo (here) suggest that glacier loss is largely caused by human activity affecting the climate system.

VERDICT

False and misleading. The number of glaciers on Earth in 1948 (Al Gore’s birth) is not known. A better indicator of climate change is studying glacier mass, which has reduced significantly over the 20th and 21st centuries.

This article was produced by the Reuters Fact Check team. Read more about our fact-checking work here.

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