Not so fast, say global experts in response to UNESCO’s glacier report.
The United Nations Educational, Scientific and Cultural Organization recently released a report entitled “World Heritage Glaciers: Sentinels of Climate Change” that stated that “limiting global warming to 1.5 C could save glaciers in two-thirds of World Heritage sites.”
That has some experts balking at the claim.
“The World Meteorological Organization has said that there really is no possible pathway to 1.5 C, so we’re already too late for that,” said Professor John Pomeroy, Canada research chair in Water Resources and Climate Change and the director of the Global Water Futures Programme.
“Already, the situation is worse than outlined in this report.”
He used the Canadian Rockies as an example of the discrepancy, stating that the region has already lost hundreds of glaciers in the national parks and adjacent provincial parks over the last few decades.
The reference glacier for the Canadian Rocky Mountains is the Peyto Glacier in the northern part of Banff National Park. It is the most intensely and longest-studied glacier in the world.
There has been a measured 330-metre retreat of that glacier since 2019, with more than 200 metres of that occurring during a summer heatwave in 2021 and the glacier ice has also stopped flowing to the bottom.
“It’s ceasing to behave like a proper glacier,” Pomeroy said. “It’s actually more like an ice mass just melting away now.”
Parts of the surface have dropped 50 metres since 2019 and on average about six metres per summer of melt downward. This significant acceleration has occurred in the last few years.
There are a few reasons behind all of this, and they all stem from global warming. Hotter summers mean that the snow melts earlier, while soot and ash deposits resulting from forest fires have darkened the glacier’s surface over the last several years.
That has changed the reflectance of that core glacier surface from what is typically 30 per cent (meaning 30 per cent of sunlight is reflected away and the rest is absorbed) to a value as low as 17 per cent, “which is as dark as a prairie field,” Pomeroy said.
“They’re absorbing a lot more solar radiation, solar energy, and melting faster as a result.”
Lastly, some icefields above glaciers such as the Athabasca and the Peyto glaciers have seen snow melting during summer periods, disrupting the creation of fresh ice at the top of the glaciers now.
“That means [the glaciers] will end very quickly,” Pomeroy said.
All of this essentially puts the world on course with the most pessimistic scenario right now, one that’s been called RCP 8.5.
RCP stands for Representative Concentration Pathways, meaning a greenhouse gas concentration trajectory adopted by the Intergovernmental Panel on Climate Change. There are four assumptive numbers ranging from 2.6 to 8.5 for this figure that are based on predictions for future socioeconomic models.
The numbers indicate a possible range of radiative forcing values measured in watts per square metre in the year 2100.
The World Heritage Glaciers report states that “Glaciers and ice caps, excluding the large polar ice sheets, are projected to lose about 30 per cent of their mass during this century for a low greenhouse gas emission scenario corresponding to a 1.5 C global warming (Representative Concentration Pathway 2.6) and about 60 per cent for the current business-as-usual high-emission scenario corresponding to global warming higher than 4 C (RCP8.5).”
The world right now is at RCP 8.5, but Canmore’s Robert William Sandford isn’t expecting that number to stay so low for long.
“At COP27 this week, it was pointed out in a report that instead of reducing our carbon dioxide emissions to 30 per cent, as we promised to do, and 45 per cent by 2030, we raised them,” said the Global Water Futures Chair with the United Nations University’s Institute for Water, Environment, and Health.
His view of UNESCO’s report was similarly as skeptical as Pomeroy’s.
“This report’s important, but there’s a number of things in it that we really need to attend to because some of them are pretty much wishful thinking,” he said.
“The situation has been so bad in terms of deteriorating climate circumstances. A lot of people feel that they have to [be] bright and happy about this in order to stay positive. My view on that is you’re not going to ‘bright side’ carbon dioxide out of the atmosphere, and you’re not going to dream climate change out of our society right now. I think this World Glaciers report needs to be looked at under that light.”
RCP 2.6 is, in his words, “the brightest of all optimistic projections.”
“I take exception to concentrating a great deal on the best of all possible alternatives, when in fact ‘business as usual’ is what we’re facing.”
Sandford said that he isn’t a pessimist, only someone trying to look clearly at the situation. Still, he has hope because humanity is essentially intelligent and has a wealth of technological tools to help it achieve its goals.
“I have hope, but I think the only way that we can genuinely possess hope and do the hard work of hope is to recognize that it’s not something somebody can give you, it’s something you have to earn,” he said.
“I think we earn it by facing and realizing the truth, and not trying to talk our way or dream our way or find other ways to just dismiss what we see happening right in front of our very eyes. I’m not a pessimist. I am increasingly realistic about what I’m seeing.”
By Scott Hayes, Local Journalism Initiative Reporter
Original Published November 18, 2022