ENVIR 280: Documenting 2014-2015 retreat of the Nisqually Glacier

I often tell my students that naturalists are society’s “canaries in the coal mine” when it comes to noticing changes in the natural world. The difference in the extent of glacial ice at the snout of the Nisqually Glacier from just one year to the next astounded us as we held last year’s photo in front of us and compared it to this year’s view.

Nisqually Moraine 2014

Nisqually glacier terminus, on October 12, 2014. For purposes of comparison to the the 2015 photo below, note the location of the light colored triangle shaped deposit on the lateral moraine opposite of the moraine the student is standing on. I’ve outlined the triangle with red. Also, I’ve attempted to trace the outline of glacial ice, which is covered in rock debris for the most part. But note how the snout of the glacier extends well beyond the apex of the aforementioned triangular deposit.

Nisqually 2015 Tim outlined

View of the Nisqually Glacier terminous, from October 16, 2015, approximately 1 year after the first photo. I have used the same red triangle from the first photo to show the location of the triangular deposit on the opposite moraine. I have also traced in the approximate location of glacial ice from October 2014, in red. And I have outlined in yellow the extent of glacial ice on October 2015. Note the massive amount of retreat and ablation from 2014 to 2015! Using subalpine fir trees (approx. 20m tall) on the opposite moraine as a scale bar, you can see that the length of the glacier has shrunken by plus or minus 100m depending on how you measure it. It has also lost a significant amount of width, and has almost certainly lost some depth too.

With my course, we always compare the current extent of the Nisqually Glacier to historical photos and evidence for past glacial activity which we can find on the landscape, but to have created our own historical photo with the class in 2014, and to go back and document change in 2015, was a particularly unique opportunity. No doubt, the warm winter and record low snowpacks of 2014/2015 were a huge contributor to this striking change. Based on recent historical trends, the Nisqually Glacier will likely continue to retreat this year, but it will be exciting to go back in October 2016 to see if the retreat is as drastic as it was in the past year.

We are lucky to live in a time and place where we can see active glaciers. Seeing “living” glaciers and the landforms they create, helps us understand the history and formation of landscapes in the Puget Sound Region, and gives us insight into the effects of climate changes past and present. If the Nisqually Glacier continues to retreat at rates of 50m to 100m a year, however, it is not hard to imagine a time in the not-too-distant future when courses like ours will no longer be able to study active glaciers in this region. The Nisqually Glacier is one of the longest in the Puget Sound Region, and is about 6km long currently, if you assume its start to be near the summit of Mt. Rainier. Presumably the lower elevation portions of this glacier, maybe the lower 3-4 km of it, will be gone in the next 50 years. If I ever have grandchildren, they will not get to experience the Nisqually Glacier or other valley glaciers like it in the Pacific Northwest. Indeed, if my own children go to college and take ENVIR 280, and hike to the same viewpoint, the view they see below them will certainly NOT include glacial ice. Is this a problem for me or for society? Certainly I stand in a privileged position to be able to fret about what my view will be like, or whether my hikes on Mt. Rainier will be on ice or rock, or whether species like the ice worm (see previous blog post) will go extinct. But the loss of glaciers will have implications for society at large. Melting glacial ice keeps our rivers cold and deep, even after winter snows melt. Diminished glacier ice means diminished summer and early-fall stream flows, which will mean water conservation issues for humans, and severe consequences for aquatic life, particularly salmonid fish, which need consistent strong, cold flows all summer long. If the Nisqually River, and other rivers like it are reduced to a warm trickle by summer, this will have profound consequences for river ecosystems across the northwest.  I tend to be fairly objective in my feelings when it comes to environmental change; afterall, there is much evidence on the landscape for dramatic climate swings throughout recent geologic time, and indeed our Pacific Northwest glaciers began retreating before the onset of anthropogenically induced warming. Some species always end up as “winners” and some as “losers”. But when I think that the current acceleration of climate change and drastic warming is caused largely by the actions of humans, I have trouble not viewing the loss of our Pacific Northwest Glaciers as a tragedy. I hope that you can get out and enjoy them now, and be thankful for them, while you can.

Nisqually snout 2014

Close up of the Nisqually Glacier terminus in October, 2014.

Nisuqally snout 2015

Close up of the Nisqually Glacier terminus in 2015.

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