While out on the ice of Storsjön, Sweden, I spotted this brilliant little ledge around the entire lake's perimeter, holding up a crowd of icicles that made for some beautiful photo subjects in the arctic winter light.
The raised ice edge is a phenomenon I notice every time I'm out on the ice, and sometimes it can be so pronounced that the edge is almost raised enough to walk under. I suspect that the edge is created after the lake first freezes, and the underlying water level drops. This occurs because there's a reduced discharge into the lake, due to all the precipitation being held as snow and ice on the ground's surface. When the level drops, the banks of the lake and any rocks just beneath the surface catch chunks of ice and hold them up as the rest of the ice surface drops. This leaves an exposed ledge, and liquid water underneath which soon freezes as well, although in some areas the water underneath the ledge hadn't frozen yet on this occasion. The icicles could be the liquid water that the ice was originally floating on dripping off as the ledge became exposed, only to freeze on its way down. These could also have been triggered by a short melt event.
In the second photo, the ledge on the right of the photograph is held up by a rock and is completely isolated from the main bank.
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