Extremes of Canadian Multi-Day Precipitation Accumulation

The detection and attribution of trends and variability in precipitation extremes has been identified as an important indicator of global climate change. In particular, both regional and continental scale changes in multi-day precipitation events can have serious impacts on several environmental and economic activities such as agriculture. In this investigation, the spatial and temporal characteristics of the maximum number of consecutive dry days and the greatest 3, 5 and 10-day rainfall amounts (as a percentage of annual total precipitation) are generated for the periods 1900-1998, and 1950-1998. Trend analyses are performed for the selected multi-day climate extreme indices and the results mapped and examined. The computation is based on the recently created Canadian Historical Rehabilitated Precipitation dataset (Mekis and Hogg, 1999) which contains rehabilitated daily rain and snow values for nearly 500 stations across Canada. Preliminary results indicate considerable spatial variability over the country with some regional patterns evident.

Mekis, Éva and Bill Hogg, 1999: Rehabilitation And Analysis Of Canadian Daily Precipitation Time Series. Atmosphere-Ocean 37(1) 1999, 53-85.