Can someone explain the ice out process?
Why does it seem that 12" of ice will be there one day and not the next? It doesn't seem to slowly melt away. As it deteriorates, does it get heavier than water and sink to the bottom?
One reason thick ice can disappear so rapidly is that it sometimes it becomes very weak (ex. due to "honycombing") although it still remains quite thick. In this case, much of the volume of the "ice" is actually water. A good wind can often break weak ice up very rapidly. I've personally watched a lake here in Madison go out over the course of lunch. The volume of ice blown to shore from a 2-3 mile fetch of lake was remarkably small (a mound perhaps 3 feet high).
iceout
The official (whatever that means) date is 4/6/04.
ICE OUT
Can someone explain the ice out process?
Why does it seem that 12" of ice will be there one day and not the next? It doesn't seem to slowly melt away. As it deteriorates, does it get heavier than water and sink to the bottom?
It's complicated...
It's a complicated process. I'm looking forward to hearing what people say.
First off, ice is always less dense that liquid water (at least in the temperature regimes we're interested in):
http://tidepool.st.usm.edu/crswr/ice.html
One reason thick ice can disappear so rapidly is that it sometimes it becomes very weak (ex. due to "honycombing") although it still remains quite thick. In this case, much of the volume of the "ice" is actually water. A good wind can often break weak ice up very rapidly. I've personally watched a lake here in Madison go out over the course of lunch. The volume of ice blown to shore from a 2-3 mile fetch of lake was remarkably small (a mound perhaps 3 feet high).
Cheers,
Geoff Sobering
DN US-5156