The serious study of avalanches began half a century ago, following

two major lines of investigation: a deterministic approach, inspired

by the theories of fluid mechanics, and a statistical approach, both well

known by all specialists in the field.

This book explores a new conceptual approach, closer to hydrology

than hydraulics, which relies solely and rigorously on field data from

the avalanche path studied. This approach is clarified and compared

with both the deterministic and statistical approaches. The authors' past

and current research implementing this approach is presented: analysis

of the bulk rheology of certain avalanches, the elaboration of new

conceptual models validated by comparison with field data,

and a methodology for determining extreme events by extrapolating

the knowledge garnered from past events. Statistics add an important

dimension to the book, with standard operations such as fitting statistical

distributions on random variables and other newer components such

as the analysis of avalanche triggering probability.

The first nine chapters present the research carried out by the Snow

Avalanche Engineering and Torrential Erosion Control Research Unit.

As the exploration of these topics is far from finished, Chapter 10

examines a number of research projects that could consolidate the basis

of this apparently very promising approach.