UKC

Last time I was skinning up the Glacier d'Argentiere there was a helicopter buzzing around overhead. Underneath it, hanging by a rope/chain, was a framework that looked like it was made of scaffold tubes. It was probably far more sophisticated than that though. It slowly flew back down the glacier in a parallel/line search pattern.

We wondered if it was sonar or something and if it was mapping crevasses/snow depths. It didn't seem in a hurry and no rescue teams were out, so we assumed it wasn't a recco/transceiver search, but we didn't really have a clue. So what was it doing?

If it was in fact mapping snow depths/crevasses, does anyone know if the maps/data are public? I'd be interested to see them if possible.

In reply to NottsRich:

Interesting, I would suspect LiDAR would be the most useful tool for glacial surveys (to a 3 or 4D sense), but these systems are relatively small and wouldn't require such a ghetto sounding set-up.

As for data availability, surveys are often expensive and resulting data is likely to only be available to industry and academia. Not to mention the requirement for specialist programmes to even view it.

In reply to NottsRich:
When was that? What colour was the helicopter?

In reply to GrendeI:


You couldn't measure snow depth with LiDAR, you need a GPR (Ground-pentrating Radar) set-up. I'd imagine they we're measuring snow thickness, you can't really find out a lot about crevasses when they're covered/filled with snow.

In reply to ianstevens:

ah, of course!

Then I guess it was much like this...

http://www.rst-group.biz/index.php?id=94&no_cache=1

In reply to GrendeI:

It does match the set-up described by the OP, and must be a study with some cash behind it to use a chopper rather than lugging round loads of heavy radar kit. There is a (relativley) long-term met station on the Argentiere and accompanying mass-balance record, so getting a glacier wide snow profile could well be one of the next steps.

As for avalailbity of data, it would take a few years to write-up and get any work through the peer-review process, but a lot of geoscience journals are shifting to open-access, so it may well be availible to the non-academic. Not that the paper may be accessible in the sense that it would require some pre-exisiting knowledge to fully appreciate.

In reply to ianstevens:

could be linked to the Laboratoire de Glaciologie et Géophysique de l’Environnement de Grenoble
see e.g.
http://www-lgge.ujf-grenoble.fr/ServiceObs/images/PlaquetteArgentiereY.pdf

In reply to NottsRich:

Did the device henging below the chopper have two big sharp cutters spinning round and was there an oil pipeline running up the glacier? And did you bump into Sophie Marceau and Pierce Brosnan on the Montets platform?

In reply to GrendeI:




Yep, that looks very similar. The one I saw had a shorter rope/cable, but was pretty much the same otherwise.


Jon, sorry, I can't remember what colour the helicopter was, but it was back in early March this year.


If you can use GPR to measure snow depth, then presumably the 'base' it's measuring the snow off is the more dense glacial ice. Surely that would show the location of crevasses, because wouldn't they would show up as sudden spikes of increased snow depth?

Doug, that's an interesting link - thanks. It was scanning in pretty much the exact area marked 'Profil 7' on that map.


Either way, I definitely didn't see James Bond up there!