BELLINGHAM, WA (MyBellinghamNow.com) – A concern among climate change-focused scientists is the size and presence of glaciers. Washington is home to some of the most heavily glaciered mountains in the lower 48 states of the U.S. In an interview with My Bellingham Now, WWU Geology Professor Doug Clark speaks about what he has seen in his decades of observations on Mount Baker.
Emma Toscani: Glaciers are a source of climate regulation on our planet, and we have a lot of glaciers in our backyard. Here to talk with me about the glaciers on Mount Baker is WWU Geology Professor Doug Clark, who does a lot of research on the ice structures and climate change. How are you doing today?
Doug Clark: I’m doing great. Emma, thanks for having me.
ET: Of course. So, can you give a little background on what’s going on with Mount Baker’s glaciers? How many there are? And the major footnotes of what we’ve seen in some of your studies.
DC: Sure. Well, Mount Baker’s the second most heavily glaciated volcano in the Pacific Northwest, behind Mount Rainier, which is the most glaciated, and it’s, I actually don’t know, the true number of glaciers. Depends on how you divvy them up, because essentially they’re almost all touching each other. So they’re basically one large glacier, but with tongues coming out at the bottom. But they’ve got about 12 to 15 glaciers, and at least for the last 100-150 years, they’ve been pretty steadily retreating, with a few little readvances here and there, but mostly, they’ve been retreating, and it’s not a small retreat. They’re, in many cases, several kilometers shorter than they used to be 150 years ago.
ET: Is that something that could be attributed to human-active climate change?
DC: Yeah, it’s sort of a combination of both natural processes in the earlier end especially, and the most recent stuff almost certainly is mostly attributable to anthropogenic climate change and greenhouse gas emissions that we’ve been putting in. 1850 was sort of the maximum of most glaciers in the North Cascades, including on Mount Baker. And that was at the very height of what they call the “Little Ice Age,” this natural phenomenon that caused glaciers around most of the world to advance beyond where they had been before, and then they started retreating after that. Mount Baker followed that same trend, and was pretty heavily retreating even before we started putting a lot of greenhouse gasses in the air, but now, most of the retreat is almost certainly due to climate change effects from anthropogenic, human-caused climate change.
ET: Can you speak to what’s happened in the last like, I don’t know, 10 years? Has it increased significantly, or is it just as steady as it has been over the last century?
DC: Yeah, no, it’s a really good question. And I take my students in one of my classes – my fall glacial geology course – we go up to the terminus of the Easton Glacier on the southwest side of Mount Baker each year. And I started doing that back in the early 2000s and in that time, in the early 2000s, the glacier had undergone one of these small, little readvances. So, the front of the glacier is all steep and crevasse and very angular. It was so steep we couldn’t even walk onto it as a class; we’d have to have axes and ropes and crampons. But since then, it’s retreated almost about a quarter of a mile, I would say, at least in just the last 20 years or so. And now the front of the glacier is just this thin, tapering wedge that you can just walk onto without even crampons. You can just walk right onto it, and that’s the sign of a rapidly retreating glacier. In one season alone, it retreated almost 100 meters, so 300 feet or so – the length of a football field – in one season back about five or 10 years ago. Pretty remarkable changes and not for the better for the glacier.
ET: Snow accumulation is another sign of changing environment for the glaciers. What can you tell me about snow accumulation that’s happened on Mount Baker in the last handful of years?
DC: So glaciers are formed anywhere where you get more snow accumulation every winter than the amount of snow that melts every year. And so, if you do that over a bunch of different years, the snow stacks up one layer upon the other, and eventually compresses into ice, which, when it gets thick enough, starts flowing downhill. So all glaciers have what they call an accumulation zone up higher in the mountains, typically, and an ablation zone, where most of the snow and some of the ice start melting down below. Pretty much at Mount Baker and pretty much all throughout the North Cascades and most of the world, for that matter, that change between accumulation and ablation has been moving up. So the accumulation area has been moving up. The accumulation areas have been getting smaller and smaller. And that’s true at Mount Baker. Doesn’t happen every year. Some years are really bumper years, like our record year of ’98-’99, a while ago for most people, but it was when Mount Baker Ski Area had the biggest accumulation in the world. It’s still the world record that year. The glaciers didn’t lose any snow. They were snow covered all the way through the whole summer, even on that year. So that was a great year for glaciers, but it’s only one year, and glaciers take many years. They average out the accumulation pattern and ablation pattern over many years, usually a decade or two before you see a significant change overall that the accumulation areas, the areas of net snow accumulation, is moving upslope, and the ablation areas is also moving upslope. So, glaciers are just shrinking because of that.
ET: And what are some ways that we can measure glaciers?
DC: Yeah, that’s a good question. There’s several ways that glaciologists have been using over time. The traditional way is to go out there and actually visit the glacier in the height of the accumulation season. The end of the winter, basically around here, it’s usually April, early May, where there’s the thickest snow pack out. They go out there, hike onto the glacier, ski onto the glacier with a steam drill, install a bunch of these long plastic poles into the glacier, and then measure how thick the snow is from that winter, as well as down where the top of the ice is, and then they come back again several times a year, usually by at least once in the end of the summer season, the melt season, and measure how much snow is melted and/or snow and ice combination down in the lower part of the glacier. And then they combine their data, and they spread it over the entire glacier, and estimate how much snow and ice is gained by the glacier and how much has been lost. That’s the traditional way. It’s a really labor intensive and expensive and only a very few glaciers in the North Cascades have had that traditional type of measurement. There are several other ways to do it, but one of the newest ways that one of my students worked on recently was using drone imagery. If you fly drones over the glaciers, and there’s this new set of programs called structure from motion, where they combine these thousands of drone photos into a fine, stereoscopic view, or three-dimensional view of the glacier surface, and they compare the winter, early spring drone survey to the late summer drone survey, and they can actually subtract one from the other and see how much snow and ice is being lost or gained based strictly on flying some drones overhead. Potentially way cheaper. There are some problems with it, or limitations that we haven’t quite overcome yet. But there’s a professor down at University of Washington, David Sheen, who’s been doing it up on Easton Glacier on Mount Baker for the last 10 years or so. And so I’m looking forward to hearing his results as they come out in the next couple of years.
ET: What have you noticed in your time, like taking up students and stuff in the last handful of years?
DC: I would say the rate of retreat of various glaciers around North Cascades, not just the ones on Baker, has been accelerating, and that’s because of a combination. I actually just looked up just before coming here, looked up some of the climate patterns right around Whatcom County that are recorded in various weather stations and SnoTel sites, and the overall trend is even though overall precipitation hasn’t really changed dramatically, the snow-water content, so the amount of water in the snow pack over the course of years, has been decreasing. So what that means is more of that precipitation is falling as rain rather than snow up in the mountains, and that’s not good for glaciers. At the same time, the average annual temperatures have been climbing significantly over time, too. So that combination of warmer temperatures and less snowfall means glaciers should be retreated, as we are seeing. So it’s clearly a combination of the two different main driving processes on glaciers that is driving this retreat. It’s not just warmer summers, it’s not just drier winters or anything like that. It’s a combination of both those.
ET: Why does it matter that we go and measure these glaciers and track their retreat?
DC: That’s a great question. Here in the northwest, especially, glaciers are one of our key reservoirs for our water supplies. Certainly, Bellingham relies on meltwater from the Deming Glacier, which is on the west side of Mount Baker. A big portion of the water that is supplementary put into Lake Whatcom comes out of that Deming Glacier. They have a pipeline that redirects water from that glacier into Lake Whatcom and supplements our water supply as those glaciers retreat,. Eventually, the amount of water coming down the rivers is going to decrease, and especially the times that the glaciers are melting the fastest – late summer – is also like right now, our driest time of the year, and so that’s a time where we don’t get a lot of precipitation, but we need water in our rivers, and we’re using a lot of water for irrigation and whatnot. And so glaciers are this key aspect of our water supply system and power generation and fisheries as well. There’s a whole bunch of other resources rely on that require that late summer glacial meltwater flow. Big concern is, as these glaciers shrink and in some cases disappear, we’re gonna have a change in the hydrology of our river systems and our water supplies.
ET: So what can water managers do in light of that? I mean, that’s not exactly your field, but do you have some ideas of what we can do if the Deming Glacier does put less and less water into our water supply?
DC: You’re right. It’s not my expertise. We have a hydrologist on our staff, Bob Mitchell, who actually he and his students do study that there’s not much you can do about shrinking the glaciers unless we really do a much better effort at turning around our greenhouse gas emissions, because that’s sort of going to be baked in for a while. But there are things you can do about trying to keep the water cooler for salmonoids by increasing the riparian zones, these tree-covered corridors along our major rivers that help shade the water, keep it cooler, reduce evaporation. We can change how we manage our water supply in the reservoirs. We do have, to some extent, and again, not my expertise. I think there are things you can do, and then other ways to store water comes down from our rainfall events in the fall and the spring, maybe put them into groundwater recharge systems, et cetera. So we have some sort of late summer story. So the key for glaciers’ effect on rivers is that late summer stream flow. So that’s the area we’d have to really accommodate.
ET: Is there anything that you wished I had asked you about?
DC: Well, there’s, I always like to tell my students a couple of fun facts about glaciers, and one of the ones that I talk about pretty much every class I teach that has any glacier involvement at all, is that the Washington has one claim to fame in sort of the glacial world, is that we’ve got one of the only advancing glaciers in our state. And it’s not because of a climate change issue. It happens to be the crater glacier at Mount St. Helens. And the only reason it’s advancing still is it’s a baby glacier just got born after the 1980 eruption finished, and so it had this perfect north-facing bowl that’s shaded from the southern sun in the summertime, and it accumulates lots of snow in the wintertime. And so this glacier has been growing and growing for immensely over the last 30-40 years since the eruption, and it stayed there even after the 2004-2008 eruption, which didn’t melt the glacier away. It actually just caused it to surge forward. So that’s kind of a fun fact is that we do have this one glacier advancing, but it’s getting close to where it’s going to be in equilibrium with the climate. And once that happens, it’ll probably turn around and start melting backwards again, just like all the other glaciers. But for right now, it’s still advancing. As far as I understand.
ET: What can we learn from looking at this baby glacier?
DC: Well, I mean, it’s unusual in the sense that we have to see a glacier grow from scratch. It’s a little bit hard to work with, I think, because it has so much rubble in it. It’s not like you get an ice core out of it or anything like that, because there’s just too much rock and debris in it. But I think there’s potentially some aspects of the glaciology that would be a really interesting study. Again, I’m not a glaciologist, so it’s a little hard for me to say, but it’s a cool thing. I’ve had students make studies of air photos, historical photos, to see how fast it advances, how thick it’s getting. There’s a bunch of different things you can use with that glacier that might inform more about what happens when a glacier advances and retreats again.
ET: Well, I really appreciate your time, Doug. Once again, this is Doug Clark from the WWU Geology Department who specializes in studying glaciers and climate change, among many other things. This is Emma Toscani with KGMI News.
