Researchers fail to dig out enough avalanche data

While we thank Dr. Röggla for communicating his perspective on our study, we would like to take this opportunity to clarify the methodology of our analysis and the relevance of our conclusions.1 The direct comparison between the Canadian and Swiss and datasets was used to illustrate that the shape of the avalanche survival curve is not universal, but rather strongly affected by local characteristics. The diverse character and limited amount of background information on the two cohorts, however, did not allow a more detailed comparison of potential underlying reasons. Instead, we performed comparisons among subpopulations of the Canadian dataset where more detailed records were available and the subgroups were less heterogeneous. These comparisons revealed that trauma primarily affects the survival probability at the early stages of burial and that more maritime snow climates were associated with an earlier onset of asphyxia. Debris density is strongly related to climate, i.e. snowfall amounts and air temperature, and could therefore be a plausible cause for this observation (as demonstrated in previous investigations), but we did not claim to demonstrate a direct association as density information was not available.

Limitations in avalanche accident records currently prevent us from examining the contributing factors to avalanche survival in more detail. Better information on the condition of avalanche victims at extrication, resuscitation measures, injuries of survivors, and environmental conditions are crucial for improving our understanding. It is our hope that our article will provide the necessary impetus for improved data collection and more research in this direction.