Cascade Glaciers - then and now

[Lowell_Skoog]

Here's a photo composition showing the summit of Forbidden Peak in 1979 and 1996. Notice the retreat of the Inspiration Glacier snout. I have another picture, taken from a slightly different angle in 1986, which shows little change from 1979. So, the demise of the Inspiration snout occurred in less than ten years!

 

[gslater]

That's an excellent side-by-side comparison. Sad to see things melting away like that...

[philfort]

A cool, but depressing webpage:

http://www.nichols.edu/departments/glacier/befaft.htm

[Lowell_Skoog]

Someone asked me what time of year the two pictures were taken. The left picture was taken July 15, 1979. The right picture was taken July 28, 1996. My brother Gordy is on the left; my brother Carl is on the right. Both shots were taken at the end of the Torment-Forbidden traverse.

[klenke]

The pictures also highlight the changes in climbing fashion, gear, and safety:

Wool sweater on the left, probably Gore-Tex on the right

Canvas rope on the left, perlon or nylon rope on the right

No helmet on the left, helmet on the right

[Necronomicon]

Natural, or man-made?

[Lowell_Skoog]

Here's another composition showing the opposite view, from Eldorado Peak. The edge of Moraine Lake is just out of the picture at the bottom. The dates are August 11, 1979 and July 2, 1996. Unfortunately, I don't have any late season pictures of the Forbidden Glacier snout from recent years, so it's a little harder to compare them. But the recession is pretty obvious.

 

[philfort]

Here's the snout in late September 2001:

 

 

Almost looks like it advanced a tiny bit between 1996 and 2001... the little snow-covered bench coming in from the left in the 1996 photo ends right at the snout, but the snout is a little below that in 2001.

Edited August 10, 2003 by philfort

[Lowell_Skoog]

philfort said:

Almost looks like it advanced a tiny bit between 1996 and 2001... the little snow-covered bench coming in from the left in the 1996 photo ends right at the snout, but the snout is a little below that in 2001.

 

Thanks for the picture Phil. Boy, the glacier sure looks withered. I'm not sure which snow bench you're referring to, but I notice a little rock buttress to the right, which seems to show the snout in about the same place in both pictures. I have a shot from late June 2002, which looks very similar to my July 1996 shot.

 

Some Cascade glaciers seem to be "surgey" over time. I've seen pictures from the 1950s of the Le Conte glacier (below Sentinel Peak), which ended well above the valley of Flat Creek. During the 1980s-90s, a narrow lobe of that glacier extended to the valley bottom. I believe the lobe is disintegrating now, but I haven't seen it for a couple of years.

 

Also, thanks for the link to before-and-after photos. I notice that William A. Long is credited for some of the photos. Long wrote several articles about Cascade Glaciers in Summit magazine in the 1960s. He was a 10th Mountain veteran and Long's Pass (near Mt Stuart) is named for him. His widow still lives in Cashmere.

[Dru]

I should have an AFTER for ya of the glacier between the peliades and American Border Pk. back from the lab sometime this wk. you can compare it with the 60's BEFORE shot in CAG III. it melted a fair bit...

 

OTOH I am currently looking at some air photos of the silverthrone gl. in central coast mts where the glacier has not receded at ALL In 50 yrs . must be more snow there

[JoshK]

Dru said:

I should have an AFTER for ya of the glacier between the peliades and American Border Pk. back from the lab sometime this wk. you can compare it with the 60's BEFORE shot in CAG III. it melted a fair bit...

 

OTOH I am currently looking at some air photos of the silverthrone gl. in central coast mts where the glacier has not receded at ALL In 50 yrs . must be more snow there

 

I was reading an article 6 months or so ago and apparently the examples of glaciers surging over the past 100 years or so are few and far between. One of the examples, however, was the blue glacier on olympus, which has apparently been growing, along with a few in scandanavia. Their explanation was warmer weather patterns often bring an increase in precip, so for coastal regions which recieve absurd amounts of precip, it is enough to make up for the increased melting. I wonder if your example, Dru, falls in the same category.

[Dru]

yeah i'm reading the papers on that. ya got any journal article refs on that send PM.

 

also more heating = more evap = cloudier weather= less sunlight=less melting.

[fern]

the term 'surging' in glaciology refers to a particular

type of periodic fast-flow behaviour. It is not directly

related to climate factors, as evidenced by the fact that

each surging glacier follows its own 'clock'. It also is

not related directly to the health of the glacier, since

during a surge event the snout will advance at the expense

of ice storage in the accumulation zone - i.e. the volume

of ice doesn't change it just redistributes. I could be

wrong but I don't think there are any surging glaciers in

the lower 48, they are a polar/subpolar phenomenon.

[JoshK]

fern said:

the term 'surging' in glaciology refers to a particular

type of periodic fast-flow behaviour. It is not directly

related to climate factors, as evidenced by the fact that

each surging glacier follows its own 'clock'. It also is

not related directly to the health of the glacier, since

during a surge event the snout will advance at the expense

of ice storage in the accumulation zone - i.e. the volume

of ice doesn't change it just redistributes. I could be

wrong but I don't think there are any surging glaciers in

the lower 48, they are a polar/subpolar phenomenon.

 

fern, I may have been using the wrong terms, this certainly isn't my area of experitese. If I recall correctly the article was saying that the blue glacier was "growing" and becoming more volumptious (I love that word ) as the years went on. Again, I may have misread, misunderstood, etc.

[j_b]

It also is not related directly to the health of the glacier, since during a surge event the snout will advance at the expense of ice storage in the accumulation zone - i.e. the volume of ice doesn't change it just redistributes. I could be wrong but I don't think there are any surging glaciers in the lower 48, they are a polar/subpolar phenomenon.

 

which indeed suggests that surging behavior could be related to glacier health.

[fern]

which indeed suggests that surging behavior could be related to glacier health.

 

Nothing in my statement makes any suggestion of the kind. If you have a point to make feel free to do so explicitly in your own words.

[j_b]

not much of a point really. i was only trying to express an idea without belaboring it. in a few words, if surging glaciers are inexistent at lower latitudes, it suggests that surging is dependent on climate and glacier health. that's all.

[Lowell_Skoog]

I climbed Eldorado Peak last weekend to test a new camera and update my pictures of the Forbidden Glacier. Here's another composition, rendered in black & white this time:

 

[Dru]

attached is pleiades and larabee north side glacier

 

looks identical ice extent to beckey ca guide vol III p. 55

[catbirdseat]

The forbidden glacier looked more VOLUMINOUS in the past as opposed to "volumptious". I think Josh was thinking of the word VOLUPTUOUS. Of course that is a very good word too and I can understand why he might like a similar sounding word like "volumptious".

[Fairweather]

I've noticed some of the ice cascades on the north side of Johannesberg no longer join at their termini as they once did. (As shown in Beckey's green-book photos.) They have each retreated into their own pockets.

[j_b]

a little context.

 

abstract by josberger and bitlake: glacier mass balance and hydrology in the north cascades

 

http://www.ecy.wa.gov/events/hg/abstracts2003.pdf

 

"To understand the response of glacier mass balance to fluctuations in atmospheric circulation, the U.S. Geological Survey (USGS) has measured the winter, summer, and net mass balances of South Cascade glacier, located in the northern part of the Cascade Range, for the past 44 years. This record, one of the longest such records in the world, shows a dramatic reduction of glacier extent and volume as the mass balance responds to short-term climate fluctuations. From 1959 to 1976, the average annual net balance was -0.15 mweq (meters of water equivalent), with positive and negative balance years. The two-decade period, 1976 to 1995, was one of rapid ice loss, averaging -0.90 mweq per year, with most years having negative mass balances. Recently, 1995 to present, the glacial recession has slowed to -0.28 mweq. This long-term trend correlates with the changes in the Pacific Decadal Oscillation, as it shifts from a cool phase into a warm phase and back into a cool phase. Short-term climate fluctuations, such as droughts and El Nino/La Nina events, as characterized by the Southern Oscillation Index, also correlate with the short-term variations observed in the mass balance record."

[fern]

Global Historical Climate Network

 

your tax dollars have paid for this nifty time wasting site where

you can plot graphs of precipitation and temperature data

from weather stations all around the world, even your

Cascades backyard

 

I plotted up some for Winthrop that look like the

late '60s early '70s had some high precip years, but it

was drier in the '80s ... if this was a general trend

across the cascades then you would expect glaciers to have

suffered.

[not_a_climber]

Here are some photos showing how the South Cascade Glacier receded from 1960 to 1992.

 

A couple of other relevant links:

1999 USGS data

South Cascade Glacier Express