(Un)Frozen Ground

 These pictures are by, and courtesy of  Dr. Vladimir Romanovski:



A sinkhole, where an underground ice wedge has melted. For scale, Vlady is ~1.85m (6'3") tall. Why he wants to stand on ground that looks about to collapse underfoot I don't know.....guess it must be a hockey-playing, Russian Permafrost Researcher thing. Maybe that's why there aren't many...



This picture doesn't do justice to just how DEEP sinkholes like this are. Yes, that's solid ice under their feet.



I think this is a pic of part of Tanana Flats (south of FBX) where permafrost has pretty much melted out...

Here's something pretty neat:

I think here the 'active layer' (id est, that which melts and re-freezes every year) has slid clean off the underlying ice. Saturated with water, and lying on a low-friction permafrost layer, it just let go....



.....and just folded up at the bottom of the slope. Wikkid.



There's a human being in this one for scale. The rolls of tundra-turf are ~2m high.