"Cryosphere"



- Cryosphere refers to any portion of the Earth's surface where water is in solid form, including glaciers, ice caps, ice sheets, sea ice, snow cover, frozen rivers, lakes, and permafrost. The Cryosphere is closely linked to the Hydrosphere and plays a crucial role in the ecosystem and our everyday lives.
- I've chosen the name because Cryosphere encompasses a wide range of ice around the world. This blog is meant to chronicle not all glaciers, but those that I experience and photograph in my travels. My vision is to visit and write about as many glaciers and other ice forms as possible while I pursue knowledge and share experiences of a beautiful world of ice. I hope you enjoy the photographs and follow along as I go!

14 May 2017

08. Castner Glacier - 14 May 2017


Every glacier I visit in my travels is unique and intriguing in it's own way. Sometimes I have the privilege of spending an entire day, or multiple days, exploring the intricate details of a glacier. Others, I may have only a short time to spend on the ice. Either way, the idea of seeing another glacier always excites me and the experiences stay in my memories like few other things in life will. My trip to the Castner Glacier was unexpected and short, but provided an interesting perspective on something I had yet to witness in person.

The summer of 2017 started with yet another long drive from Utah to Alaska. 3,000 more miles driven for the privilege of spending the third summer in a row in sunny Alaska (actually, it would turn out to be one of the wettest summers on record in the Matanuska Valley). The drive is beginning to wear on me, and I question every time I travel it whether or not it's worth it. Am I doing more harm than good? 3,000 miles is a lot of fuel to burn to spend a summer exploring glaciers, which in a way, I'm contributing to their demise by making the trip. Should I stop going, admire from afar, and hope to spread the word of the damage being done without such first-hand experience and evidence? I have a lot of time to think on these long days behind the wheel. At least for now I feel I have good reason for making the drive.

In addition to running photo operations alongside MICA guides, I had resolved to explore as many other glaciers as I could possibly get to that summer - I'm aiming to walk on and photograph as many as I can in the increasingly bleak and shortening existence they are destined to. As global temperatures rise and weather events and climates become more erratic and unpredictable, who knows how long they will be around to be enjoyed. Certainly access to many of them will be getting much more difficult in the coming years. By the end of 2016 I had managed to tally up only 8 glaciers, starting with the easiest ones to walk to in Alaska and Canada, mostly along the route I would already have been driving to and from Alaska. In 2017 I would employ new methods of Alaskan transportation including backpacking, kayaks, a train, four wheelers, and wading through belly-button deep, newly melted glacier water (complete with icebergs floating by) to access 10 more glaciers that summer alone. Then a trip to New Zealand (in progress as of this writing) will hopefully add on a few more to kick off 2018. But you'll have to wait to hear more on those stories in future Chronicles!

Bound for Alaska in May, 2017, I was itching to get an early start to my glacial checklist, and was heading out to scout out a few glaciers in an area of Alaska I had yet to visit. In a remote section of Eastern Alaska, between Delta Junction and Glennallen, the Richardson Highway cuts through the Delta Mountains, part of the broader Alaska Range. My hopes were that the maps were still somewhat accurate, meaning that several glaciers would be within possible hiking/bushwhacking distance of the highway. I hoped to get eyes on some or all of the 4-5 glaciers mapped out to within a mile of the road. Then I could hopefully return with some eager guides later that summer to check them off the ever-increasing list. I carried a bit of hope that I could hike to at least one on this early recon mission, but I didn't want to be too disappointed if time wouldn't allow, and anyway, most glaciers would probably still be covered with snow at that point. I told myself just seeing even one glacier would suffice for this early in the season, and I would have more reason to return for one long trip later on.

The trouble with maps in Alaska is that the last time the USGS bothered to really compile information was some time in the 1950s, with a revision in the '80s. It's hard telling what parts of the maps were revised when, but I suspect that the boundaries of what classified as a glacier in either of those decades may have changed somewhat in the last 35-65 years. No wonder I couldn't locate any glaciers from the highway. I did, however happen upon an unmarked dirt road fairly close to the toe of one presumably incorrectly labeled Gerstle Glacier (further research after the fact would reveal it to be the Castner Glacier). The road didn't go far, and got very rough very quickly. I parked the truck before a particularly narrow and washed out section of trail, near another vehicle which looked to be camping there, and proceeded to follow the "road" on foot. A few hundred meters along, I met a middle-aged couple coming the other way. I excitedly asked if they had seen the glacier, and they responded by telling me they saw a cave, but didn't go in. Said it looked "a bit unsafe" from a distance. A glacier would be cool, an ice cave was something totally unexpected and even more exciting. Still not entirely sure what they meant by 'cave,' I jogged the rest of the trail until it faded into obscurity in the wide bed of a braided river. As I hopped and wound my way over and around boulders and scrub brush along in the general direction of the river, shrubs became shorter and shorter until they ceased to be seen. Plant life in general changed from tall and diverse to a few short flowers like sweet pea and other new sprouts. They call these pioneer plants - they are the first to begin life in geologically new or devastated areas, and they are generally a good indicator of a nearby receding glacier.

When I began to notice the area in front of me changing, the first clue that I was looking at a glacier was not a valley full of shining white ice like the Matanuska Glacier - it was a hole. The granite rocks and boulders all across the valley suddenly rose up from the valley floor in an incline, and in one steep section, directly above the river, was a large, cavern-like hole through glacier ice. This must be the 'cave' the couple had spoken of. Honestly, it wasn't much of a cave - more of a death trap - "a little unsafe" was quite the understatement. The hole had been melted out of the ice by water running under and through it. This was an exit moulin, the opposite of what I spend my time climbing into on the Matanuska Glacier. All that water goes in, it has to come out somewhere.


Looking down into the large cave at the toe of the Castner Glacier with water, mud and rocks falling in from above


The ice above the cave was melting from above and below, forming a steep angle covered in rock and mud which was all visibly sliding down and dropping into the river below. The scary part was even higher up: above the steep slope were more rocks, much larger, perched on edge, precariously waiting for the ice to melt from under them. In a few short minutes I witnessed at least 20 softball size or larger rocks dislodge themselves and tumble the 10 meters down the slope to crash to the rocks and river below. Any one of these (not to mention the much larger boulders also ready to fall any second) would have been enough to kill a person trying to walk into the opening. And to what end? The only ice to be seen was in the roof of the cave. It was far from the beautiful blue ice everyone expects when they excitedly ask their tour guide if they're going to see any ice caves. No, this ice was different. Or rather, what was on top of it was different. The moraine covering ensured no light reached the ice to illuminate that magical blue color seemingly from within. Many glaciers I've seen have had sections covered by rocks and debris, but the Castner brought the idea of moraine covering to a new level for me. There was so much rock I could never have guessed there was ice under it all if not for the otherwise inexplicable cavern in the slope. My only thought at that point was that this must all be "dead ice" - slowly melting in place - long since separated from the active glacier above it. However, it would be odd that this much dead ice would still be frozen with an exit moulin this large and with this much water running out from under it. More exploration was needed.

Too excited and impatient to wait and return later with things like friends or proper glacier travel gear, I pressed on, wearing what were basically tennis shoes. Skipping the potentially deadly cave visit - it only went in a few meters before wading through the river would be required anyway - I scrambled my way up a less-steep slope around to the side. I quickly discovered that under the thick covering of rock was more ice. It's hard enough tromping up a 40 degree scree slope and slipping back half a step for every stride, the only thing worse is when you add ice to the equation! I was literally on hands and knees crawling forward in the sliding rocks, at times just brushing the moraine aside to look for imperfections in the ice below to place my hands and feet on. The 10 meter high hill became an agonizing battle, but I was too stubborn to slide back to the bottom and find a way around. At least the icy slide down would be faster.

My view from the top of the hill didn't improve much. Above it was another hill - thankfully less steep - and above that, another. The further I walked the less it seemed there was even a glacier to be found. Maybe the dead ice with the cave was just an isolated patch, but then, there was far too much water flowing for that to be the case. I was looking at rolling hills of boulders and ground up rock and mud, but no ice could be seen. It looked like the valley was filled by a glacier, except it was all rock. Could it be that the entire glacier was covered in moraine? I dug down through over half a meter of loose rock and silt, getting colder and colder as I dug down, until yes, glacier ice was eventually revealed. Further walking saw more signs of ice, some peeking out from below the moraine in the steepest sections of hills.

On the steep slopes of ice, moraine is unable to stick so the ice shows through


Only when I climbed to the top of the highest dune (the only way I can think to describe these hills of moraine), nearly a kilometer from where I had scrambled up the first slope near the cave, could I look up valley and see actual white-ice-glacier far off up the valley. Everything around me was just dunes of brown and tan granite rock. There were even large shrubs growing up here. Wait, shrubs? On top of the ice? Continuing on, I finally crossed the valley to the south to find a massive slope, the steep angle keeping the majority of the moraine from sticking in place, and the extra sun exposure on that side ensured that it received more heat, furthering the effect of differential melting to cut away the slope.

A sort of 'side canyon' formed along the South end of the Castner Glacier where the ice has melted faster than what was covered in moraine on the main flow of the glacier.

This finally convinced me that the entire section I had been walking on was a part of the active glacier. However, it must be moving incredibly slowly for the shrubs to take hold and grow to heights taller than me! And what could have caused all this moraine to fall all the way across the valley and cover the entire width of the glacier? There must have been massive landslides many years ago to bring this much rock down with the ice. Or perhaps the glacier was formerly much thicker, deflating tremendously over time and, in the process, dumping in massive amounts of rock from both sides.

I've read about rock-covered glaciers, and even heard that there are places where trees are growing on top of ice - some say the Matanuska has a forest on top of a large section of ice to one side, nearest Lion's Head. However, the difference between reading in a textbook, hearing stories, and witnessing something like this first hand can not be overstated. The same should be said for glaciers in general. It is not enough to read about them and enjoy them from afar. Go out there and witness their magic first hand. Stand at the edge and stare in awe, or hire a guide to bring you out and show you the intricate details of the massive beast. No, don't stop at one. See many glaciers. See all that you can because they are all unique and enchanting in their own way and each one will leave you in awe - even if it is at first hidden from sight.



Afterthoughts:

Further research after my hike revealed that, indeed, the glacier is covered with more moraine than usual, apparently when studied in the 1950's there was an outcropping or nunatek in the middle of the glacier far uphill, where potentially all the excess debris came from. At the time, there was actually white ice below all the debris, resulting in a nearly 100' tall rise of moraine mid glacier! All the clear ice below the debris pile would have presumably melted in the last 70 years as the glacier receded. However, all the moraine would have, and still does, insulate the ice to prevent it melting as quickly in the covered area. The Journal of Glaciology link below contains this information, as well as confirming the plant life growing on top of the active glacier, even at that time. While I can find little info on the rate of flow, I would guess it must be rather slow to continue to accumulate plant life over the years.

Castner Glacier Statistics:

My First Visit: 14 May, 2017
Type: Valley Glacier
Location: Delta Mountains (subrange of Alaska Range) along Hwy 4 between Paxson and Donnelly
Source: Delta Mountains between Triangle Peak, Black Warrior Mt., White Princess Mt. and Old Snowy.
Length: 19 km
Width: ~1 km
Flow: Unknown
Status: Retreating
Access: Walking through rocky stream bed and some larger boulders, some of the hike can be eliminated with high clearance 4x4 driving, but could be walked from Richardson Highway


More Information:

Journal of Glaciology Article:
https://www.igsoc.org/journal/2/14/igs_journal_vol02_issue014_pg277-280_276.pdf

Another Photographer's account of the change of Casnter Glacier
http://ianajohnson.com/castner-glacier-hello-but-goodbye/

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