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9 July, 2000

July 9, 2000

Matanuska Glacier, Alaska

Yesterday as Ben and I made our way back to the pickup point we stopped at our ISCO station just to double-check on things before leaving. We immediately noticed that the two streams of surface runoff nearby had risen considerably in the hour that we’d been away to the moulin. It’s amazing how much the streams rise and fall during a 24 hour period due to the sun’s action on the glacier. One of the streams seemed to be dumping out fairly close to our ISCO tube now and so we moved it away to another part of the vent. We certainly didn’t want our samples to be diluted any more. It was still going to be over a half hour before our first sample was to be collected and so we headed off, satisfied that everything was looking good.

During that afternoon my thoughts kept turning to the ISCO and what we might see when the samples were finally inspected. At the same time I was excited about those prospects I was also being frustrated by the workings of the fluorometer. It was good to have excited anticipation of the ISCO samples to offset that frustration.

It’s a bit hard to explain but on the ride out to recover the samples my excitement was really building inside. Could we possibly find a moulin/vent connection on our first attempt? Earlier attempts by other researchers have found this to be a difficult task and so I was trying to not get my hopes up too much. As we walked down the trail to the vent I couldn’t wait to open up the ISCO and peer inside. When we got to the point where we crossed a small runoff stream earlier it looked quite different. The day’s increased runoff had cut deeply into the ice channel and it was maybe six inches lower than before. In looking at the walls of the channel one could notice the daily pattern of melting in the form of alternating horizontal ridges and valleys in the ice.

After finding a new way to cross this little stream we approached the ISCO. We opened the lid to the ISCO and looked down at the LCD display: “Fatal Error: Distributor Arm Jammed”. Ben and I didn’t know what that meant but it sure didn’t look promising. Surely we got some samples in there. After quickly pulling off the top to reveal the sample bottles our worst fears were confirmed. Each bottle was bone dry. Nothing!

Setbacks are to be expected no matter what game you’re playing. Although we are very disappointed in this outcome we have learned quite a bit from it. Our first mistake was not opening the ISCO to check that everything inside was free to operate as it should. As it turns out when the backpack holding the ISCO was taken off, the ISCO fell to its side. All the lids to the sample bottles are left inside and some of these got into the distributor arm area causing it to jam. We decided to program it to collect every five minutes so we could stay and watch it work properly. We then discovered our second mistake. As the time came to pull in a sample we watched the water travel a short way up the tube, stop for a bit and then retreat back into the vent. We then found that it was programmed to pull samples through a ten foot sample hose and ours was fifty feet. The sample would have never made it to the bottle even with no distributor arm problem. We’ve carefully reviewed everything and checked it out. We now believe that it will operate as it should.We will try again Monday and find out.

Later in the morning we headed off for Wasilla to get showers, groceries, other supplies and to do laundry. Ben and I will also buy a lot more salt for our project. A special treat when going to town is stopping off for “restaurant meals”. Tomorrow we’ll haul another load of salt out to the moulin. Till then.....

Marvin Giesting


On a recent hike to North Vent I stopped for a bit to enjoy the scenery. Believe it or not this is part of the Matanuska Glacier and it is still on the move! Recall in the aerial photo (July 7) that a large area to the north is covered by rocks and silt. Plants can eventually take hold and thrive even though it is solid ice not far below.


A little higher off the North Vent trail I saw this interesting scene. Can you guess what's going on here? There is an abundance of flowers on the left. On the right they seem to be widely scattered. If you look closely in the distance in the upper left you can see the same thing occuring. A clue: you are looking somewhat to the east.


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