Logbook entry: Sauna cave sampling trip (2016-12-04) at Sauna Cave
About happenings on Dec. 4, 2016, Tehnuka Ilanko wrote:
It was a clear morning. We left around 10 or 11 am to do a full day in which we placed and collected samples in Sauna, to avoid a return trip. Instead of the low route that I believe is the usual one to Sauna, we took a higher one, turning off the path we take to the upper warm ground, through the rocks. We approached just uphill and parked a short distance away.
The old entrance on the east that Tobias remembered was closed so we went through a higher tower opening on ITR side (NW). Tom set up two lines with two snow picket anchors each, as well as connecting them to an ice screw via webbing as a pre-tensioned front tie. He backed one of the anchors up with his snowmobile. We prussiked up to the opening and rappelled down using Petzl stops while he belayed us. We learnt the hard way to be careful when using a dynamic rope for rappelling... The cave entrance was to the right when rappelling - on exit I noticed another possible cave area to the left, though it may have just been a small hole.
The downhill side was colder and the rocks were sharp for crawling around in - we measured more CO2 on the Testo higher up, where it was warmer, so we sampled in the upper part of the cave. Even in the entrance area there was a large vertical temperature gradient, from below 10C holding the probe by the ground, to almost 30C holding it above my head.
The back (uphill) was much more humid. There were two ways up – one a scramble up steep and loose rocks with a squeeze at the top, which was to the left, and the other a climb up some boulders, to the right (much easier). We crawled around with the temperature probe and testo, looking for a suitable vent. They all appeared to be in the rock roof, rather than near the ground. The one we ended up using was on the far wall, near the right hand entrance to the hot room. The room continued up and back but the vent was at about 43.5C (I found it by standing in the right place and noticing my head was getting hot). The testo read about 5900 ppm CO2 at the vent. We called it Sauna ATom later found another vent around 44C just down from Sauna A.
In order to sample a cooler vent, we set another probe near the base of the scramble entrance to the hot room. Vent was 12.5C; testo read 2796 ppm CO2. I collected water from roof drips near Sauna A, as I believe these are condensed steam as opposed to melted ice as is likely in other caves.
Also sampled cave air near the entrance - temperature range here was from 9C at the height of the entrance, up to over 25C when I held the probe above my head.
We then put on all our layers again and climbed out using handled ascenders and a foot loop. We derigged and drove back around 6 pm.