Building histories of climate extremes at Canada's biosphere reserves 1935–2005

Previous studies examining climate have focused on what is called a “climatology” of a region or the 20 to 30 year average in temperature or precipitation. “Climatologies” are important when studying the long-term trends in temperature and precipitation, or comparing differences from one region to another. However, traditional “climatologies” do not assist in understanding the year-to-year changes and extremes in climate - information that supports how communities adapt and respond to a variable and changing climate. This study builds “histories” of climate extremes using the 27 core climate indices developed by the Expert Team on Climate Change Detection Monitoring and Indices of the WMO Commission of Climatology (CCl) and the Climate Variability and Predictability (CLIVAR) project, and distinguishes which years were particularly wet, dry, hot and cold. These histories are built from climate data that has been homogenized to adjust observations, if necessary, so that the temporal variations in the adjusted data are caused only by climate processes. These histories are built for Canada's 13 biosphere reserves – areas that are ecosystems recognized internationally by UNESCO's Man and the Biosphere (MAB) Programme as part of a global network. Biosphere reserves, through the nature of their management structure of “round tables”, are areas where sustainable development is an applied concept. This paper presents the approach to building histories of climate extremes for 70 years of climate data at each of Canada's 13 biosphere reserves, and how these histories are used to for climate change adaptation.