One Oregon Glacier Declared Dead: How Many Will Follow?

In October, the Clark Glacier which has sat on the southwest side of the South Sister mountain in the Cascade Range was reported dead. Members of the newly formed Oregon Glaciers Institute organized a service on the steps of the capitol building in Salem, as well as a much smaller hike up the South Sister to say goodbye.   

There is not a single agency responsible for monitoring the health of glaciers in Oregon, so Aaron Hartz and Anders Carlson started the Oregon Glaciers Institute in May of this year. The hope is that the Institute will help raise public awareness of Oregon’s glaciers as well as be able to study the glaciers themselves.  

Oregon’s glaciers aren’t doing well. They’re decreasing in size which doesn’t bode well for ecosystems and economies that depend, even indirectly, on the water that comes from them.   

Glacial Facts  

Glaciers are basically rivers of ice, whose run off feeds non-frozen rivers and benefits many different environments.   

Of the impact of glaciers, Carlson said, “They feed the streams in late summer, sustaining hydro power, watering livestock, irrigating fields, cooling streams for salmon and trout. And those cool streams reduce the impact and severity of forest fire. Basically, all of Oregon’s major industries, livestock, farming, fishing, logging, all depend on glaciers. Likewise, those ice-covered peaks are part of Oregon’s identity.”  

So how do we know that the glaciers in Oregon are dying?   

According to Carlson, “A glacier is dead when it no longer moves under its own weight – this means it is less than 100 ft thick.”   

However, there are other ways of identifying a dead glacier that doesn’t involve measuring its thickness. Carlson said a lack of crevasses indicates that the glacier is no longer moving, a lack of glacial sediment in the meltwater flow shows that the glacier is no longer eroding its bed due to lack of movement, and a concave edge means the ice is no longer flowing forward.   

And how old was Clark Glacier? According to Carlson, we don’t really know.   

“It is definitely older than 200 years as the glacier was much larger than in the 1950s during the late Little Ice Age that ended in the mid 1800s in Oregon, with Clark Glacier retreating from its moraine,” Carlson said. “So, I would say it was at least many hundreds of years old and easily over 500 years old. But beyond that educated guess, it is hard to say from what we know about the history, and pre-1850s in particular, of glaciers in Oregon.”  

Oregon Glaciers Institute  

The first step for the Institute was to conduct the first census of the Oregon glaciers since the 1950s. Back then, the United States Geological Survey created topographic maps that are still used today. The outlines of the glaciers in Oregon were present on those maps so the OGI was able to see how many of the glaciers once existed. They hoped to determine the changes in size seen over the last 100 years to see how the glaciers have responded to climate changes within that time.    

Based on the USGS, glaciers could be found near Mt. Hood, Mt. Jefferson, North Sister, Middle Sister, South Sister, Broken Top, Wallowa Mountains, and Mt. Thielsen. OGI found evidence that, in the recent past, glaciers could have been found on Three Finger Jack, Mt. Bachelor, Diamond Peak, and Mt. McLoughlin. These former glaciers coalesced into ice caps, while the glaciers in the Wallowa Mountains expanded to fill the valleys of the range.  

In the future, Carlson said, “We hope to set up a mass balance observational network in the Oregon Cascades where we directly measure the amount of snowfall a glacier receives each year and how much ice is melted by the end of summer. From this, we can assess how healthy a glacier is. And from these combined observational data of past glacier change and measurements of current and future as we will make these measurements each year going forward, assuming state/federal support along with donations from concerned citizens, we can project the future viability of Oregon’s glaciers.  

So far, the cause of the decline of Oregon glaciers hasn’t been fully studied, however Carlson believes it has something to do with warming temperatures and climate change. Because of this, the best way for people to help the glaciers is by limiting their carbon footprint.   

Carlson, who is not shy about the lengths we need to go to protect these valuable resources, said, “Basically, we need to stop carbon usage like a decade ago. The forcing of Oregon’s glaciers deaths is a global forcing. We need to reduce the amount of carbon dioxide in the atmosphere so every little bit helps.”   

One person lowering their carbon footprint can have significant impacts, he added.   

In the end, we need to stop driving gas cars or using public transportation that uses gasoline or natural gas and stop flying in airplanes,” Carlson said.   

By Kyra Young