Think Out Loud

The high-altitude impacts of climate change on Mount Rainier and Mount Hood

By Sheraz Sadiq (OPB)
Oct. 5, 2023 8:42 p.m. Updated: Oct. 18, 2023 9:51 p.m.

Broadcast: Wednesday, Oct. 11

The Coe and Ladd glaciers on the north side of Mount Hood have lost 50% and 80% of their areas, respectively, in the last 120 years. This photograph was taken by a team from the Oregon Glaciers Institute in September 2023 during a photographic survey of Mount Hood's glacial ice cover which found that climate change is accelerating the loss of Mount Hood's glaciers.

The Coe and Ladd glaciers on the north side of Mount Hood have lost 50% and 80% of their areas, respectively, in the last 120 years. This photograph was taken by a team from the Oregon Glaciers Institute in September 2023 during a photographic survey of Mount Hood's glacial ice cover which found that climate change is accelerating the loss of Mount Hood's glaciers.

Anders Carlson/Oregon Glaciers Institute


Mount Rainier in Washington state is covered with nearly 30 square miles of glaciers and icy patches - more than Mount Hood, Crater Lake and all other volcanic mountains combined, from British Columbia to Northern California. But climate change is taking a toll on Mount Rainier’s glaciers, according to a study published in June. It found a 42% reduction in glacier area from 1896 to 2021, and officially removed Stevens glacier from the park’s inventory. The situation appears worse for the glaciers at Mount Hood, according to a new photographic survey completed last month by the Oregon Glaciers Institute. It found that the seven major glaciers at Mount Hood had receded an average of 60% over the past 120 years, and that roughly a quarter of that loss happened in just the last 20 years. Joining us to discuss the toll climate change is taking on the ice cover in these iconic and popular Northwest peaks are Scott Beason, a park geologist at Mount Rainier National Park, and Anders Carlson, the president of the Oregon Glaciers Institute.

The following transcript was created by a computer and edited by a volunteer:

Dave Miller: This is Think Out Loud on OPB. I’m Dave Miller. Mount Rainier is covered with nearly 30 square miles of glaciers and icy patches, more than Mount Hood, Crater Lake, and all the other volcanic mountains from British Columbia to northern California combined. But climate change is taking a huge toll on Mount Rainier’s glaciers according to a study published in June. It found a 42% reduction in glacial area over the last 125 years. The situation is even worse on Mount Hood, according to a photographic survey that was just completed. We start with Scott Beason. He’s a park geologist at Mount Rainier National Park. Welcome to the show.

Scott Beason: Hello.

Miller: I want to start with some basics. What is a year in the life of a healthy glacier like?

Beason: It’s a good question. Glacier is a balance between accumulation of snow and ablation, or melt, of the snow in the summertime. So in the winter time, you get a massive accumulation of snow. And in the summertime, you lose quite a bit of that snow through processes like snow melt and the sun hitting the snow and things like that. And when you get a period of time where there’s enough snow that lingers around from year to year, the next year you get another accumulation of snow, and then another year and another year. And before you know it, it’s kind of like a layer cake of snow. And that turns into a thing called firn, a year’s accumulation of snow. And then enough time goes by and that turns into glacial ice. It’s a situation where we have snow that accumulates and does not melt. And then over those processes, turns into a glacier.

Miller: How does that compare to what’s happening on Mount Rainier right now?

Beason: What we’re seeing at Mount Rainier is that we’re getting more rain falling than snow, and we’re getting less snow accumulating. So in a given year, we expect to see a certain amount of snow, and we’re seeing less of that. The glaciers of Mount Rainier are in a situation where they’re not getting recharged with the snow that they need to be. And we’re basically losing glacial ice over time. We won’t have the recharge in snow, and then the summer snow melt melts down into the glacial ice underneath of it, and basically you’re losing the glacial mass over time.

Miller: The data that makes up the study that you recently released goes back to 1896. Were glaciers shrinking at the turn of the 20th century?

Beason: Yeah actually, they were. From 1896 to the next survey that we had, 1913, we did lose ice between those periods of time. So we were losing ice for sure in that time. But the rate that we’re seeing in the last decade or two has really accelerated based on the historic data that we have.

Miller: How much of that loss that we’re talking about is recent, as opposed to 120 something years old?

Beason: You’re looking at rates. So in the last six years, we’re seeing a rate of about 2.5 times that estimated in the previous period. That was from 2009 to 2015. And we go back from the 1896 period to the 2021 period, you see a rate loss of about 0.2 square miles per year. And in the last period, it’s about 0.3. So it’s about doubling that rate that we have had from the historic period.

Miller: And you get the sense that even that is accelerating?

Beason: It is definitely accelerating.

Miller: I mentioned that finding that more than 40% of glacial area was lost between 1896 and 2021. But if I understand correctly, that doesn’t include the depth or the thickness of the ice. What happens if you include that third dimension, how much volume has been lost?

Beason: Volume can be really difficult to calculate in the glacier just because it’s really hard to actually see through the glacier itself. But when we look at the volume reduction, we’re seeing a reduction of about 52% in that 125 year period. We’re definitely seeing more ice melting when you add in that third dimension. The math is more complicated, but definitely a lot of ice loss on the mountain.

Miller: The data in this latest study went up to 2021. Do you have any sense for what’s happened in just the last two years?

Beason: We didn’t really look at the last two years. We basically do the survey whenever we have a good opportunity to get clear satellite imagery and funding to do the surveys. Looking at and talking to other researchers, there’s a couple other glaciers that we’re looking at, we’ve basically removed them from our survey at this point. So, the Van Trump Glacier and the Pyramid Glacier are probably no longer considered a glacier in the park. Our survey kept them in place just because we still saw evidence of the glacier there. But since then, it’s just continual loss.

Miller: Why do you do this? What are the many things that are at stake when glaciers disappear?

Beason: Glaciers are a source of clear, fresh, cold water that’s provided to rivers in the park. There’s a lot of aquatic species that depend on that cold water for their habitat. Bull Trout is one example of that. There’s a study just recently done that looked at the anticipated effects of climate change in the next century, to see what would happen with the Bull Trout habitat as we lose that glacial ice. It’s pretty stark for that species specifically. They’re gonna lose their habitat. They’re gonna have to move to different locations or they’re just gonna die out.

The other thing that I have an interest in is a process called a debris flow, where as you retreat, glacial ice, you’re leaving behind sediment that is basically super steep, it’s not sorted, it can fail any time. You get a surge of water or something that happens in the glacier and it can pick up that material and mobilize into what’s called a debris flow. Then the debris flows can go downstream, affect park infrastructure, and really damage old growth forests, infrastructure, it can affect people, visitors, and the employees that work here at Mount Rainier.

Miller: And they can be deadly, right?

Beason: They can be. Thankfully so far, they have not been. There was a debris flow in 2015 where we had a visitor that was taking a video and it went right by them. And it was sort of terrifying seeing that video. It’s cool seeing the process, but at the same time, it was terrifying that they were that close to it.

Miller: We are talking about climate change here, about specific sites, in this case on Mount Rainier, being impacted by human actions on a global scale. And obviously the biggest thing we can do as a species is to stop burning fossil fuels. But are there other specific interventions for saving glaciers?


Beason: This question we get frequently is “what can we do with glaciers in the park?” There isn’t a lot that we can really do. Monitoring is what we’re really good at doing. In some locations in Europe, they talk about putting tarps and stuff on glaciers. But when you talk about 29 square miles of ice, that’s just not feasible. Really, the long term solution is to look at climate emissions and see how we can change those over time, watch and see how it happens with the climate from there.

Miller: Scott Beason, thanks very much.

Beason: Thank you.

Miller: For another perspective on melting glaciers, we turn now to Anders Carlson. He is the president of the Oregon Glaciers Institute. Welcome back to the show.

Anders Carlson: Thank you, Dave.

Miller: Can you remind us what the Oregon Glaciers Institute is?

Carlson: Sure thing. It’s a small nonprofit formed in 2020, volunteer citizen scientists looking at documenting the changes in Oregon’s glaciers and the impacts they have on our environment and ecosystems.

Miller: My understanding is that you heard a promo for our conversation that we were going to be having with Scott Beason, and you said, “I have news to share with Oregon about Mount Hood.” So, what are the surveys that you recently completed?

Carlson: So, we finalized two surveys. One is just documenting how many glaciers remain in the Oregon cascades. And then what the recent one that I contacted you about was in 2003, a mountaineer and emergency room doctor in the Portland area, Doctor Steve Boyer, for posterity’s sake decided to go out and measure the location of the termini of glaciers on Mount Hood, and also photograph them. And he probably at least at one point held the record for the number of summits on Mount Hood as well. And he shared this information with us a few years ago. and we then decided this summer to go out 20 years later and repeat his survey to document how much these glaciers have changed in the last 20 years. So kind of a 20 years of the 21st century glacier change on Mount Hood. And the last official published documentation of glacier change on Hood was finalized in 2001 to 2004.

Miller: So almost 20 years later, you did this again. So tell us the bad news.

Carlson: Oh, the bad news is that there’s been massive loss of ice on Hood. At a bigger perspective, about in the last 120 years, 60% of the major glaciers on Hood have lost 60% of their area. Now, that’s over the last 120 years. 25% of that occurred in the last 20 years. And so, roughly, of the area lost in the last 120 years, 40% of that occurred in the last two decades. It’s been a rapid increase in the rate of glacier loss in the first two decades of this millennium. Just to put some numbers on it, up to the turn of the millennium, glaciers on Hood were retreating at about 3.5% per decade of the area loss. In the last 20 years, this has increased by 3.6 times to 12.5% of the area loss per decade.

Miller: What we’re talking about is just a worse version of the exact same dynamics that we are hearing about on Mount Rainier, which I guess makes sense given that we’re talking about a significantly lower elevation mountain on Hood, and a little bit further south, warmer in two different ways. How did you actually carry out this survey? What were the physical challenges of doing this?

Carlson: Good question. When Steve did this back in 2003, he took his time going around the mountain and just climbing up the different drainages on various weekends in the late summer, early fall. We don’t have that luxury anymore 20 years later. So we had to go for it when you could have a window with no forest fire smoke, which has greatly reduced the ability to conduct such research in Oregon, because the best time we’ll get glaciers is late summer, early fall. That’s also when our skies get choked with smoke and you shouldn’t be outside.

So we found a window to do it in. And then instead of just going up the different drainages, going around a cone, we’ll circumnavigate Hood above treeline. The intent was to walk every ice margin around the mountain.

And that was really difficult. For one, the glaciers are retreating fast, and so there’s a lot of water there, and that has made the ground unsure. Like Scott just mentioned, debris flows are increasing. And then on top of that, the rock fall above the glaciers is dramatically increased as well. You see it on the glaciers themselves where they’re becoming debris armored and covered with a rock fall. But it’s also coming after us. We had to actually bail on one of our pathways because bowling ball sized rocks are flying down randomly every five minutes onto Newton Clark Glacier. And then we saw a giant landslide occur. We videotaped it, and it is just right out of the glacier just shooting down right where we wanted to go. So it has become very, very dangerous to conduct this work in the late summers because of the warming climate that’s removed the snow and ice protecting the underlying rock from falling down.

Miller: So, essentially for thousands of years, these huge rocks have been kept in place by ice. Now the ice is melting and the rocks are just falling down the mountain.

Carlson: The mountains are literally falling apart with the loss of snow and ice on them.

Miller: What about Oregon’s other glaciers? I’m thinking in particular about Central Oregon on Mount Jefferson or South Sister or the other Sisters?

Carlson: Good question. They are in worse shape than Mount Hood. Mount Hood, just like you mentioned before, Hood being further south and lower elevation than Rainier making it warmer,  Hood is also the most resilient mountain within the state of Oregon to climate change because it’s the tallest and furthest north. As you go south, the problems become worse. In Mount Jefferson this summer, the glaciers outside of Whitewater Glacier had no snow on them at the end of the summer. And so they’re in very bad shape, they’re not getting any refurbishment of snow. They’re on a starvation diet. When you go down to the Three Sisters region - South Sister, Middle Sister, North Sister and Broken Top - they’ve been in that kind of state for five to six years now at a bare minimum. In short, it’s gotten too warm in that region to sustain glaciers for a long period of time. They’re going to disappear in that region in the current climate. It’s already too hot in Oregon to have glaciers in the Three Sisters region.

Miller: What does all this mean for people who love being on mountains for skiing, for hiking, for whatever?

Carlson: It’s a dramatic loss. It’s fundamentally changing the way we view the mountains in Oregon. We have iconic snow covered peaks that we see on the horizon and we go to and get reprieve in the summers for going up and getting a ski. You can’t do that anymore. And if you go later in the summer, you might get hit by a rock. It’s shortening what was our year round ski season that we brag about. Timberline doesn’t operate now throughout the whole year. They do a good job of maintaining the Palmer Snowfield on Hood, but they cease operations in August now versus letting people ski into September and only stopping just to repair the list before the winter comes.

The streams will start running dry in the late summers, and it’ll impact what Scott was saying there, the salmon, the trout. It’s gonna make water wars increase because you’re gonna have hotter streams with less water in them, and a conflict between withdrawals for agriculture and ranching and drinking water versus keeping the streams flowing and cold enough for salmon and trout species to survive. So, it’s not good at all.

Miller: What has this work been like for you emotionally? To take part in these surveys that put numbers to what you can already see with your naked eye?

Carlson: In a way it’s cathartic because you could see it happening. And when we started the Oregon Glaciers Institute, the main reason was that nobody was paying attention to this in the state of Oregon. We can now at least put numbers on it and make people be aware of what’s happening. Basically, the climate’s already too hot. And so we need to cool down from where we are if we want to keep Oregon the way we’ve known and loved the place we live in. So this is one of the best ways to document and make people aware of how the climate is changing and will impact our way of life in this state.

Miller: Anders Carlson, thanks very much for your time. I appreciate it.

Carlson: Thank you.

Miller: Anders Carlson is the president of the Oregon Glaciers Institute.

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