Quantitative relationship between weather seasonality and rock fall occurrences north of Hope, BC, Canada

The relationship between rock falls and weather conditions has been widely recognized and attempts have been made to develop weather-based approaches for rock fall hazard management. This dependency of rock fall occurrences on weather suggests that rock fall trends and their associated risks will vary following climatic changes. In this regard, tools that quantify the relationship of weather seasonality and climate with rock fall trends provide an opportunity to forward model potential variations in rock fall trends considering diverse climate scenarios. This paper illustrates the application of one such tool along a section of a transportation corridor through the Canadian Cordillera. von Mises probability distributions are fitted to monthly trends of precipitation and freeze-thaw cycles and combined to develop a probability density model of rock fall occurrences. The methodology is outlined in detail and the model shown to fit the rock fall database with a correlation coefficient of 0.97. Further, the paper discusses limitations of the approach and potential opportunities for improvement, encouraging the use of the method at other sites and building a robust case study database for further enhancement of the approach.