Comparison of Precipitation Characteristics Across the Continental Divide in the Canadian Rockies

Precipitation events that bring heavy precipitation to the Canadian Rockies are a critical aspect of the region's water cycle and can lead to extreme events such as the 2013 Calgary flooding event. The impacts of these events are highly dependent on the type of hydrometeors and their distribution near the continental divide. To improve our understanding of these processes, a field campaign called Storms and Precipitations Across the continental Divide Experiment (SPADE) was conducted during May and June 2019. Instruments to measure precipitation aloft and at the surface were deployed on each side of the continental divide and manual observations of precipitation particles were collected. This study focuses on the data collected by the disdrometers, snow microphotography as well as the precipitation gauges. The Micro Rain Radar (MRR) is used to detect the precipitation layer aloft and the location of the top of the melting layer. Results showed that when the air temperature was above 0 °C, drier conditions as well as higher ratio of rain occurred on the western side. On the other hand, the eastern side received higher amounts of snow and various types of ice crystals were reported such as capped columns composed on dendrites instead of plates. Overall, this study contributes to a better understanding of precipitation processes in the Canadian Rockies to better prepare for extreme events.