Part of Horizon, Prof. Danielle George looks into how avalanches are caused, and creates one herself. Avalanches kill hundreds of people every year, and with climate change there are becoming harder to predict when they will occur. This programme follows George and a team of scientists who in March this year deliberately created an avalanche in the Canadian Rockies in order to get a better understanding of them. There are also interviews with those who have survived avalanches. Avalanche: Making a Deadly Snowstorm is on BBC Two at 21.00.