Ice caves of Migovec II

Tanguy Racine, Gabriella Koltai, Christoph Spötl, Jana Čarga, Zdenko Rejec

After almost a full year of waiting, I felt the nagging urge to go back to Migovec. Christoph, my thesis supervisor and Gabriella a colleague from Innsbruck joined a small taskforce whose primary aim was to visit M-17.

I contacted Jana from the JSPDT a couple of weeks beforehand, so that we could make sure the borders were open between Austria and Slovenia, but also to sort out the sleeping arrangement at Planina Kal. Using the hut as a base would make the logistics of the trip that much smoother. The trip would be a short one, two full days on the mountain, with travel on either side.

Tuesday 7th July

Christoph and I left Innsbruck in the early afternoon and picked Gabi up from Villach train station (she was returning from Hungarian holidays), enjoyed an ice cream and carried on driving towards the Predel Pass. Once in Slovenia, we followed the course of the Soča, enjoying occasional sunbursts over the great limestone massifs as we made our way to Tolmin. Mala Boka, the waterfall resurgence in Kanin was impressive as ever.

As we met Fratnik in Paradiso, we received a text from Jana and Zdenko: they were already climbing up to Kal and would be preparing some dinner for us; it was a lucky turn of events. We said goodbye to Fratnik and drove to Ravne just as the last of the daylight disappeared.

There followed the walk up to the hut under a darkening sky gradually clouding over, but as we stepped into the warm and bright interior of the hut, we were handed a swig of žganje made with Echinacea, a medicinal flower I am told is apt to boost our immune systems. We also gladly accepted the offering of pasta bolognese and plunged into animated discussions of the history of the Slovene nation and country before turning in.

Wednesday 8th July

Zdenko was first up the following morning, mowing grass below the hut to clean up the hiking trail. We made a quick breakfast and re-packed our bags, redistributing some of the gear with Jana and Zdenko. They were going to appraise the container and see whether it could be moved higher up on the mountain, so their accompanying us as far as the bivi made perfect sense.

We set off under the bright morning sun, climbing up the zigzags and the scree slopes to the Migovec Plateau, dwarf pine still wet with dew, edelweiß in full bloom everywhere. At the already snow-free bivi, we quickly foraged through the barrels and plastic bags to find the two 'research' ropes I had left since last year; this was more or less easily done. The bolting hammer however, well, the less said about it the better. It took a veritable age to find.

Crossing the portal onto the Migovec Plateau

We then geared up outside of the M-17 entrance and threw the ropes down. One of them I only realised then, stank of something, like a dead animal or some such. It was pretty bad. Still, we abseiled down to the main chamber to appraise recent changes in snow levels and spotted daylight at the far end of the flat ice floor. The snow cone there had retreated considerably, allowing one to exit at the bottom of the M19 doline.

This was not altogether suprising - such a through way to the M19 doline had already opened back in October 2018 - and I suspected that such events might have happened at the end of summer, especially when the preceding winter is snow poor. However, with the cave already 'opened' in early July, one can expect enhanced ventilation and advection of heat into the cave, furthering the ice retreat.

On the upside, the ice shaft below was open, and a hitherto obscured section of the stratigraphy (the alternation of firn layers with or without organic material) was revealed to us. We sampled ice and wood fragments to be dated with C14. Wherever we can determine the age of the wood fragment, there is good reason to think that the enclosing ice has the same age; therefore by dating several wood fragments along the stratigraphic ice sequence, we can build a age/depth model and retrieve an apparent accumulation rate. In this way, alternating periods of snow accumulation and retreat may be determined.

Ice stratigraphy in the lower part of M-17

I had previously sampled the bottom part of the exposed ice section, as I wanted to target samples as old as possible, so this time we focused on the upper part, garnering several more wood fragments to be dated, as well as ice itself. Christoph took several pictures on the way up, of the ice layers and of the main ice chamber, where a large ice column still subsisted.

This sampling done, we exited the cave to bright afternoon sunshine and hiked back down to Planina Kal, where the cevapčiči that Jana had kindly brought up were served with polenta and ajvar, a feast. This time, the sky remained clear in the evening and to our delight bright Jupiter, followed by Saturn climbed over the Vogel ridge.

I went to bed the head full of stars, which I put down to the Echinacea schnapps. My wonderful variegated dreams collapsed into dust, as a carbon monoxide alarm went out barely two hours later. We opened the windows and star gazed a bit more. It took longer to fall asleep this time, but made it through the night we did. The main door was left open.

Thursday 9th July

The next morning we received a visit from the military helicopter at 8 am, dropping off essential supplies for the continued restoration of the third hut.

We were soon thereafter hiking up towards the Plateau, in order to check out M-15. This is another shakehole about 100 m east of the large M-17 doline. The 80's survey suggested the presence of a sizeable snow cone and importantly a crevasse between the wall and the snow. My prior experience at Planika led me to expect a drop in snow levels in the past three decades, and maybe an enlargement of the crevasse itself, allowing a good look into the snow stratigraphy and perhaps a way on.

The shaft/doline entrance of M-15, acting as a funnel for winter snow

With drill in hand, we equipped the pitch again, abseiling past the old spits and putting in stainless steel bolts instead. We landed on the sloping snow surface, leading NW into a high aven chamber. At the very far end, a 3 m drop does indeed show the ice below the snow. Unfortunately, this was very clean ice more akin to congelation (ie: drip water freezing inside the cave) rather than firn (densified snow), and it contained very few woody fragments. Not the twin to M-17 then, but a cousin perhaps. Surprisingly (or so the resurvey suggests) the snow height has not changed considerably in 30 or so years.

As to exploration potential, blocks still block the very bottom of the cave, and no ice-free or obvious downwards continuation was observed. We nonetheless completed a new survey of that cave.

A survey of M-15

Back on the surface, we returned to the Bivi to retrieve one data logger left there over the 2019/2020 winter. Out of curiosity I threw down the ropes to M-10 - in seven years, I had not yet been to the bottom - and abseiled to the snow cone. Spurred on by the description by Jack Hare in Hollow Mountain III, I looked for the way to the ice-filled chamber Let It Go, which he and Rhys had surveyed in 2015. Jack describes a large bouldery ledge in the entrance pitch; the ice plug reached that level five years ago. Now, it was possible to continue the abseil another 5 metres.

In order to reach the Let It Go chamber, I simply walked down the snow slope, barely ducking under the rock-ceiling. Jack and Rhys had needed to dig snow out of the way. The ice stalagmite was there still, as well as a shell-shocked salamander at the very bottom of the cave. Boulder floors everywhere, no obvious way on from the deepest point unfortunately. I quickly disto-surveyed the cave, drawing the wall outline on my way up to capture the scale of the snow retreat in just five years.

A survey of M-10

In the meantime, Christoph and Gabriella helped re-pack the bivi. Once out I put the ropes away and we considered our options. Evening proper was still a couple of hours away, and given its proximity we agreed to climb to the summit of Kuk to get a view of Triglav in the setting sun. The weather conditions lent themselves to this exercise excellently (see below).

We finally packed up the bivi fully, said our various goodbyes to the bivi, M-10, elephant rock, the sunset spot etc., and headed down to Kal once more in the gathering dusk. We finished up the meat left by Jana and Zdenko, almost finished the medicinal schnapps and drew up the surveys of M-15 and M-10. In the meantime Christoph sorted through the photos he had taken during the trip.

Friday 10th July

The next day, we whiled away some time clearing the place up until about midday, whereupon we started down the hill. I quickly popped into Coincidence Cave to retrieve the temperature logger data, feeling the steady 5°C air blowing out of the cave. Finally we met Jana again for a coffee in Paradiso, where we handed the keys back. A quick jaunt to the farmer's market, and we drove back north, direction Austria. No rest for the wicked!

Tanguy Racine

The action team, left to right: Tanguy, Gabriella, Jana, Zdenko and Christoph

Addendum

The hut at Planina Kal is in truth a great place to have a retreat such as this one. Through the efforts and investments of the JSPDT, it is ever cosier and practical, so thanks a bunch for letting us stay there!