Climate is important in geologic time scale. So is weather in arctic expedition time scale

Av Prof. Per Mller, PhD Nicolaj K.Larsen, Lektor Eric S.Hansen, PhD Henriette C. Linge

Climate is important in human-scale and geologic time scales. So is also weather in arctic expedition time scale. This we really learnt during the last week. The weather turned 180 degrees last Monday; from 2-3 degrees chilly winds from the sea ice in the north we suddenly had a very strong, warm wind from the south and temperature peaking at c. 22 degrees in the afternoon for two days! Very nice of course, but the result came two and a half days later. Last Friday we woke up at five o'clock in the morning with water in our tents. Our camp was at the river bank, just 0.5 m above the- what we experienced from last summer- quite stable river and just along the landing strip for the Twin Otter. We could see the river level rising with bare eyes, and quickly relocated the whole camp to the highest possible location, i.e. in the middle of the runway some 70 cm higher.

We went to bed again, though monitoring the river level each hour. Just after two o'clock in the afternoon we realized that we would be flooded in 5 hours.

Quick decision; relocate to a much higher gravel bar some 200 m north of the camp. We thus rafted and carried our +1000 kg camp and were ready some hours later, just to see the whole landing strip disappear beneath water at eight o'clock.

Since then the water level has continued to rise and our gravel bar grew smaller and smaller, and became an island yesterday. We then suspected that it could not just be the melting of snow and ice from the fhn wind situation; Nicolaj and Henriette climbed a bit up on the valley side and saw something that we have just been joking about; 25 km to the south our valley is blocked by the Sifs outlet glacier, damming a lake to the south of it at an altitude of 216 m above sea level, whereas the two lakes on our side of the glacier are just at 18 and 14 m, respectively. What if the upper lake broke trough? And that was exactly what they saw this morning; a week ago the glacier was a tight cork against the valley side, but now there was a cascading river between the glacier and the valley side, explaining why our river is just rising and rising. This could of

course get very serious for us on our small island in the river if the gap grew even wider. So once more, relocation a few hundred meters away on a plateau some 15 m higher up. Here we should be safe. However, the landing strip will never be fit for landing when we are due to be picked up at around the 26th of August.

The Twin Otter was also supposed to land today with our food ransoms for the last two weeks as we just had food left for some five days. As landing was not an option we were instead "food bombed"; food containers were dropped from the slowly approaching Twin Otter, making large splashes in the shallow water along the river, and we had to be quick about it getting the containers in before the stream took them. Most things survived, though there was a nice mixture of mayonnaise and rice between some of the cans. And we never got hold of our wine boxes that were said also to be dropped. A few hours later the Twin Otter

returned, scouting for a possible landing strip further up the valley (they can land at very odd places, just flat dry ground without boulders and a length of c. 100 meters). They obviously did so as we later saw a large dust cloud and heard roaring engines (meaning full breaks and short strip) a few kilometres away. So hopefully we will be brought home and do not have to over-winter!

Otherwise, we still have had just beautiful weather that doesn't interfere with our geologic and lichenological work. So we continue to sort out the relations between different geologic units and landforms, We just have solved one puzzle from last year: then we found a lot of mollusc shells at 40 m above sea level just lying on the ground, but not in any marine sediments. The most probable solution then was that they were just a remnant- a lag- from marine clays that once were there. However, we have now located a site, covered in snow last summer, where the shells are situated in a 1.5 m high till section! The shells and their host sediment have thus been taken up by an advancing glacier further up the valley, mixing sediments and shells with other debris, and depositing all in a till forming the end moraine ridge (see previous blogg). This tells us that the valley glacier advance is younger, and not older, than the marine sediment, which makes a lot of difference when it comes to the geologic history of the area!


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