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peltoms
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PostTue May 01, 2007 7:39 am 
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I have created a new page today at the North Cascade Glacier Climate Project site.  This page features pictures that illustrate glacier changes, as observed by hikers and climbers in the North Cascades.  All of these images will have been submitted for inclusion on this page.  These observations are an important supplement to our annual measurement programs, we cannot visit and observe every glacier every year.  The site has about 7000 visitors a month, so they will be well viewed.  The observations are critical to chronicling changes in our glaciers.  The measurements of change reported with the photograhps have been completed by NCGCP.  The photographers name, date of the picture are included.  So if you have old pictures or new ones that portray the terminus or the entire glacier that document glacier change, I hope you will submit them here.  I will then transfer them there giving you full credit.  There is no means for you to directly submit them as there is no public access to the college website. I recognize that we can gather better data and hence a better understanding together, than we can alone.  Hopefully there will be plenty of submissions and then there will be a series of pages for specific regions or even glaciers in the North Cascades, but I am not going to set that up as yet.  Here is a picture of Lynch Glacier taken in 1978 by snowshoe pioneer Bill Prater of Cle Elum.
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Scrooge
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PostSat May 12, 2007 10:07 am 
Going, going , ......
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.......... and for all I know, gone already, because I haven't been there in eighteen months. The lowest elevation glacier in the Lower Forty-eight, the Ice Caves Glacier at Big Four, is on the way out.

Ice Caves Glacier at the base of the Big Four cliff, September, 2005.
Ice Caves Glacier at the base of the Big Four cliff, September, 2005.
Ice Caves Glacier pan
Ice Caves Glacier pan

Unlike the ephemeral snow piles that form elsewhere along the base of the Big Four cliff, this has been a permanent glacier, not just a pile of snow. It's been there as long as anyone's been going there, and it used to be much bigger. Hopefully someone will have pictures of the earlier versions.

It is a real glacier. Ice forms from compression of the snow that gets piled on top every year, and then the whole mass begins to move under its own weight. The layers of ice get warped and crevasses form in the surface (no good pics of those).

Ice Caves arch
Ice Caves arch
Ice Caves arch and banding
Ice Caves arch and banding

The next two pics are just to provide a sense of scale.

Ice Caves perspective - note the people and the small cave opening on the lower left.
Ice Caves perspective - note the people and the small cave opening on the lower left.
Ice Caves perspective - this is looking out from the "small" cave in the photo on the left.
Ice Caves perspective - this is looking out from the "small" cave in the photo on the left.

As far as I know, the Ice Caves Glacier never made it to any official list of Cascade glaciers. In a few years, it won't matter, anyway.         frown.gif

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Riverside Laker
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PostSat May 12, 2007 12:27 pm 
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Technically, the Ice Caves aren't a glacier, are they? The ice doesn't flow. Would it be called an ice field?
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peltoms
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PostSat May 12, 2007 1:41 pm 
to be or not to be a glacier
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I have not been to the Big Four but if we take Scrooge's observations as accurate then it moves and has been permanent.  It would then be a glacier.  Crevasses are indicative of movement.  The pictures do not illustrate motion.  So i will remain open minded.
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mgd
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PostSat May 12, 2007 3:19 pm 
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I always figured Big 4 to be a seasonal snowfield, but this brings to question how long does it take for a glacier to form?  The one in the St. Helens crater took how many years?  Can a glacier be born in just a year or two?

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peltoms
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PostSat May 12, 2007 3:40 pm 
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Good question.  Since it takes four years at a minimum to become glacier ice once the material falls.  It is unlikely to be created faster than that.  I do know of glaciers that have formed in as little as a decade,
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Gil
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PostSun May 13, 2007 3:56 pm 
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peltoms:

Is there a "good" way to photograph a glacier? In other words, should one use normal lens, wide angle, telephoto? And what data should be provided with the photo -- time, date, elevation taken from, direction of photographer to glacier, etc?

Gil

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peltoms
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PostMon May 14, 2007 8:44 am 
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I appreciate the pictures so far and have posted many of them at NW Glacier Observers.  The key to usable glacier photographs is a clear view of either the terminus or the entire glacier.  Whether this takes a telephoto or a wide angle depends.  The only information needed is a date.
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weatherman
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PostTue May 15, 2007 5:52 pm 
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What is the status of the snow field at the upstream end of Lake Twenty-Two
on Mt. Pilchuck?  That was one of the lowest perennial snow fields
in the Cascades at an elevation of only 2500 ft.
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PostTue May 15, 2007 8:05 pm 
Columbia Peak and 76 Glacier  Then and now..
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I tried to take the same shot my grandparents did back in 1926, but my navigation skills were no better than my photography that day.

Columbia Peak and 76 Glacier   July 1926
Columbia Peak and 76 Glacier   July 1926
Columbia Peak and 76 Glacier  August 2006
Columbia Peak and 76 Glacier  August 2006
Columbia Peak  August 2006
Columbia Peak  August 2006

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peltoms
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PostWed May 16, 2007 4:22 am 
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You are a hard judge.  The foreground may not be the same spot, but the background is very close in the two left pictures.    The photograph is good, yes the lower part is dark, but that is the lighting of that time of the day.  Thanks, they are already in use on the web page.
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Scrooge
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PostWed May 16, 2007 2:21 pm 
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Hmmmm. "Ice Mass" ....... I like it, Peltoms.      agree.gif

I may well be wrong about Big Four being a true glacier, but it's certainly more than just a pile of snow. It can't very well be a snowfield, because much of its mass has been converted to ice; and somehow icefield conjures images far too grandiose for Big Four.

So, ice mass it is. For simplicity's  sake, I think I'll continue to call it a glacier. That's what Anderson and Vining did, when they prepared their map of the Ice Caves in 1980.

Extent of Big Four Glacier Caves in 1973 - Anderson & Vining
Extent of Big Four Glacier Caves in 1973 - Anderson & Vining

It's a little amusing that they chose to call it a glacier and identify it as a glacier, in spite of the fact that their accompanying article was at pains to state that it was not a glacier.

Based on what shows on the map, only the lefthand lobe has really been "permanent". Although some of the snow and ice in the other lobes sometimes lingers for several years, most of the time most of it melts completely each year.

However, as far as permanence of the lefthand lobe is concerned, compare these two pics taken 83 years apart.

Big Four Ice Cave in (fall) 1920. ...... Man standing on glacier (circled) for scale.
Big Four Ice Cave in (fall) 1920. ...... Man standing on glacier (circled) for scale.
Big Four Ice Cave in November, 2003, when the snow and ice was pretty much at the level it's been all this century.
Big Four Ice Cave in November, 2003, when the snow and ice was pretty much at the level it's been all this century.

Although there's been some erosion of the rock face, I've drawn lines along key fractures to show how similar the snow level really is.

edit - Weatherman should appreciate this, since it seems to support his "little or no change" theories.

I don't know whether or not the method of ice formation has anything to do with official glacier status. In my original post, I asserted that the compaction of the snow into ice took place because of compression due to its weight. That was an assumption and it may not be true. All of the ice might have formed due to melting and refreezing.

I don't know nearly enough physics to be able to determine whether the available mass of snow would be sufficient to compress into ice under its own weight. I've estimated the height of the pile at more than 200 feet at times that I've been there. Anderson said that, "In some years it has been nearly 300 feet high." The USGS goes that one better. The Silverton quadrangle, based on aerial photos taken in 1979 and 1985, shows a vertical mass of snow that spans 450 feet!

Big Four Ice Caves as shown on USGS map
Big Four Ice Caves as shown on USGS map

Perhaps Peltoms, or one of our other scientists, can determine if that ought to provide enough weight to produce compression into ice ...... and movement.        prod.gif

Movement is probably the real key, but once again the evidence can result from different causes. That there is movement is clear from the warping and orientation of the annual layers of ice.

Iceclimber on B4 glacier, 12-07-02 (Ice Girl photo)
Iceclimber on B4 glacier, 12-07-02 (Ice Girl photo)
B4 iceclimber 12-2002
B4 iceclimber 12-2002
Ice climber at the top of the Big Four Glacier, 12-2002
Ice climber at the top of the Big Four Glacier, 12-2002

Note that in these pics taken at the back top of the glacier, the annual layers slant down towards the front of the glacier, pretty much reflecting the angle of deposit.

Scallops - in a side tunnel of the B4 Ice Caves, 2002
Scallops - in a side tunnel of the B4 Ice Caves, 2002
Big Four Ice Cave in 1920
Big Four Ice Cave in 1920

But, in these, taken at the bottom front of the glacier, the annual layers slant down towards the back of the glacier, a significant change in orientation. ........ Ergo, movement! ........ But .......

The movement does not have to be due to any forward motion of the ice mass. It might all be due to subsidence due to melting; just an uneven settling over time. If that were true, would the "movement" qualify Big Four as a glacier?

At least one other factor might be indicative, crevassing. But, once again, although the crevasses are there, the reasons for their presence might not be "glacial". ...... In the pictures of the iceclimber, above, the moat at the edge of the glacier is a crevasse of sorts, and it was certainly a crevasse that separated the block of ice from which those pictures were taken from the main mass. Here's a more definte crevasse.

Big Four crevasse, 11-01-2003
Big Four crevasse, 11-01-2003

It's a great crevasse, but it definitely is not due to forward motion of the ice mass. It's a stress fracture, due to an almost complete void between the ice and the rock underneath it. In that, it is probably typical of most of the visible crevasses at Big Four. ....... Here's that November, 2003, picture, again.

Big Four Ice Cave in November, 2003, when the snow and ice was pretty much at the level it's been all this century.
Big Four Ice Cave in November, 2003, when the snow and ice was pretty much at the level it's been all this century.

Most of the transverse crevasses that develop are probably due to sagging of the roofs of the caves, rather than forward motion of the glacier ....... but I don't know that. Once again, perhaps our experts can comment.

Finally, here's a stratigraphic monkeywrench, apparently taken in September, 2005, just shortly after my original Ice Caves pic.

Stratigraphic confusion.twkd
Stratigraphic confusion.twkd

I cannot account for the orange stripes which appear to be radial to the center of the cave, and which also appear to slant down towards the back of the cave.

Will they help make the ice mass a glacier?        bricks.gif

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peltoms
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PostThu May 17, 2007 3:59 am 
par excellence
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Scrooge, great information to  ponder.  Unfortunately regular work dominates the next two days, and then I will provide my version of a Holmesian verdict.
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Scrooge
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PostThu May 17, 2007 6:05 pm 
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2005 bias         eek.gif

It's just occurred to me that the last year I spent any time on the glaciers was 2005, the year after the winter of 2004-05, when there was almost no snow in much of the Cacades after January 1st!

Until right now, I have been thinking that the conditions that I observed then were typical of what was going to be happening in the immediate future. Yes, the glaciers are melting, but perhaps not quite at the rate that these pictures suggest.       doh.gif

Coleman Icefall 07-30-05 ...... It's not really an ice cave.     :(
Coleman Icefall 07-30-05 ...... It's not really an ice cave.     frown.gif
Coleman Icefall grotto 07-30-05 ........ This doesn't prove anything; it's just for fun.     :)
Coleman Icefall grotto 07-30-05 ........ This doesn't prove anything; it's just for fun.     wink.gif

These are from the Coleman Icefall on July 30, 2005.  In the left hand pic, note that layers of old ice are already exposed.

Snow Creek Glacier.08-19-05 ....... Nothing left but old ice.
Snow Creek Glacier.08-19-05 ....... Nothing left but old ice.
Remnant of Snow Creek Glacier above Isolation Lake 08-19-05
Remnant of Snow Creek Glacier above Isolation Lake 08-19-05

These are from the Enchantments, pieces of the Snow Creek Glacier on August 19, 2005. The lefthand pic is the usual scramblers route up Dragontail. This year, nothing was left but a wall of ice, and very few people were attempting it. ....... Compare these pics to Ragman and Rodman's pic of the Snow Creek Glacier on the GCP site.

Sholes Glacier snowfield 09-18-05 ......... Nothing left but old snow.
Sholes Glacier snowfield 09-18-05 ......... Nothing left but old snow.
Sholes Glacier slope and terminus 09-18-05 ......... More old ice.     :(
Sholes Glacier slope and terminus 09-18-05 ......... More old ice.     frown.gif

The Sholes Glacier on September 18, 2005. Once again, nothing left but old snow and ice.

Add to those my Ice Caves pics from Sepember 4, 2005 ....... see the  beginning of this thread ...... and this one       dizzy.gif

Big Four Ice Cave 09-04-05
Big Four Ice Cave 09-04-05

.......... and you wind up with a pretty misleading story of crisis on Northwest glaciers. Yes, they're melting. Yes, some of them have disappeared already. ......... But don't hang up your crampons just yet.       winksmile.gif

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peltoms
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PostSat May 19, 2007 3:41 am 
Glacier it is
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Thanks for the pictures which are enough evidence to demonstrate that Big Four at least was a glacier.  To create glacier ice you need a consistent 100 of snow-ioe thickness in our climate.  The pressure from more than 100 feet of ice inevitably generates glacier ice.  In Antarctica it takes more with the lack of melting and refreezing, the density of the snow is lower and remains low for longer as you descend into the glacier.     This ice mass is a reconstituted glacier just as you have beneath the Cascade pass trailhead, below Joburgs north face.  Such glaciers have concave basal slopes.  This is not conducive to much motion.  Scrooge's well documented crevasses still result from differential motion even if it is from some slumping and sagging, but it is not of just the surface this extends to depth which would not occur in a snowpatch or ice mass.  The November crevasse looks like it could be a bergshrund, but even these do not form in snow patches or ice masses typically. Some of the motion is due to frontal melting and the opening of the ice caves creating a greater surface slope.  In the last picture showing the confused stratigraphy this is typical, of an avalanche chute accumulation  on a glacier.  The thickness increases tremendously as you approach the center of the chute, causing the layer to thicken toward the center of Big Four.  Scrooge I would say there is no doubt that Big Four was a glacier up to 2002, by any definition.  By 2005 it is not clear if enough snow and ice exists.  What about 2007 we had two good avalanche years, which could have helped Big Four.
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