Friday, 31 August 2012

Rae Glacier, and Dispelling Myths (with pikas!)

Common belief has it that the source of the Elbow River (which flows through Calgary and supplies about a quarter of the city with drinking water) is the Rae Glacier. Folks nervous about global warming point to the fact that the Rae Glacier is much smaller than it used to be, then get nervous that the Elbow will dry up when the glacier goes away.

This argument is problematic to me because:

  1. The common belief is false. The meltwater from the Rae Glacier supplies about 5% of the headwater creek of the Elbow. Maybe less than 5%. The Rae Glacier is not the headwaters of the Elbow River.
  2. The argument assumes that the Rae Glacier supplies a significant quantity of water to the Elbow. Also false. The Rae's contribution probably wouldn't provide more than about 10 homes with water. Rae's contribution is probably less than 0.005% of the flow that arrives in Calgary.
  3. The argument ignores a whole heck of a lot of rain and snow that falls in the entire Elbow River drainage, which supplies 99.5% of the water that arrives in Calgary.
Anyone who actually wishes to see this need merely take a 6 km hike up to the Rae Glacier, which we did last Sunday. It's an easy walk, starting with a short uphill saunter on a fire road to Elbow Lake (which is not fed by the Rae Glacier, and flows out and down the river). The fire road is popular with mountain bikers and horses, and would have been mostly uninteresting save for crossing a rockfall that was infested with pretty bold pikas. We saw at least 7 and heard many more. Some came and grabbed grass within 3' of me.
Watching out 
In the grass 
The lake itself is quite pretty.
As you arrive 
From the south shore
The lake is popular with fishermen and campers, and there's a pretty little back country campground back there, with a very high tech composting toilet (a bathroom always a nice thing to find while hiking).

The glacier is less than an hours walk up from the campground. You head up the wide, mostly empty floodplain channel of the Elbow River...
Mt. Rae in the distance. The peak on the left has no name
...which I suspect would be full at spring run off, and has the river in it on the other side. You then climb a pretty ridge with the rather awesome Mt. Elpoca in the background.
Coming up the ridge 
One twisted, bent, folded, faulted chunk of rock
Looking up the valley. Top of the Rae Glacier visible
Around here we saw a herd of sheep on the flanks of Mt. Rae.
Girls and their babies
They stayed in the same general area all day. But it was interesting that most of the other hikers we ran into didn't see them until we pointed them out.

Eventually, you pop out of all the life forms and end up in a rocky glacial basin that's so young, there's not even any lichen growing here. It's pretty sterile. Climbing to the top of the terminal moraine of the Rae Glacier, the views are nice.
Looking back from whence we came
The valley splits in two. The basin with the glacier in it, and the basin where all the water comes from.
The actual headwaters of the Elbow. Rae Glacier is to my right. 
The Glacier
This glacier doesn't look like much. It's not even as pretty as Old Goat glacier, which is a similar kind of hike, and closer to my house. But it's deceiving. Like the massive Wenkchemna Glacier in the Valley of the 10 Peaks, the majority of the glacier is covered in (and made up of a lot of) rock. In fact, in the above photo, the bowl of ice in the lower left corner is the only exposed lobe of the glacier. The main part of the glacier starts just above it. And when you walk up to it, you go from loose scree to scree that is solid because it is frozen in an ice matrix. This is interesting when its 27° outside.
Footprints in the snow 
The view from higher up 
Looking back
KC is standing on rock that is frozen in ice. This is a pretty safe glacier to walk on, with no crevasses or bergshrunds. However, there were a bunch of recent avalanches higher up than we went.

On our way back down, we went to the the actual headwaters of the Elbow. This roaring waterfall...
The Elbow River
...comes from this "spring".
The actual source of the Elbow. Not from the glacier
Hard to call it a spring. It comes out on the bedrock of a big basin.
The basin above the falls. Lotsa rock.
Way in the back of the basin is a bunch of snow. Probably was a glacier at one time, but certainly not since 1844 (see below). Now it's a névé. Look that up in your Funk and Wagnells.
KC on the basin lip, the "spring" below her 
The waterfall
Just below where KC is standing, a little trickle of water comes out of the Rae Glacier basin and joins the cascade. The Rae's meltwater was too pathetic to photograph. I stepped across it on the trail.

On the way back down to the car, we stopped and watched more pikas collect their grass.
This was a pretty little hike, similar in some ways to Sparrowhawk Tarns, in that there's lots to explore up in the basin if you feel like it. And I like any hike with pikas.

But I don't like "junk science" that tells me that the receding of the Rae Glacier will cause the Elbow River to dry up. The peak of the last "little ice age" of global cooling, and the maximum extent of the North American glaciers, was 1844, and everything's been melting back since then. I'm not going to get into a global warming issues diatribe at this point. The Rae Glacier is smaller than it was in 1844; it's probably the same size as it was before then sometime, but no one was around to take pictures. But the Elbow isn't drying up because of any of that. It's not drying up at all. And it's not going to dry up any time soon.

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