Don't breathe the snow...

[mycrofft]

http://www.thesierraweb.com/generalinfo/horseshoelake.cfm
There have been confirmed fatalities although local authorities are understandably reluctant to trumpet this:
http://articles.latimes.com/2006/apr/08/local/me-risks8

This has also been a danger in the Yellowstone area, notably Mammoth Springs (coincidence with community name near Horsehoe Lake), and the famous Death Gulch near Wahb Springs, where the 1897 exploring party found and photographed a passel of huge dead grizzlies who came to eat the other anmals killed by the gasses, then rotted into their version of Jello.

http://books.google.com/books?id=R5QCAAAAYAAJ&pg=RA1-PA632&lpg=RA1-PA632&dq=death+gulch+grizzly+bears&source=web&ots=7uP56jPtA8&sig=xep6M5MVJAJQoTC2NX2KaONrqk4&hl=en&sa=X&oi=book_result&resnum=1&ct=result

http://hvo.wr.usgs.gov/volcanowatch/2006/06_06_15.html

 

[KempoEMT]

Thats crazy

 

[mycrofft]

Yeah isn't it?

John Rogie of the USGS was an expert about Horsehoe Lake/Mammoth CA. He had a photo posted of a CO2 "waterfall'' in Italy where the gas was so thick it poured over a rock lip and was visibly distorting the rocks in the shallow depression it ran in.
Google "mazuku" and "Lake Nyos".