Changes in daily and extreme temperature and precipitation indices related to drought in Canada

The National Climate Data Archive of Environment Canada contains the official weather and climate observations for the country. Daily surface minimum and maximum temperature and daily total rain and snow observations are available from the archive for studying climate change in Canada. However, caution should be used for the interpretation of climate trends since artificial discontinuities were sometimes created due to site relocation or changes in instruments and observing practices. Based on the recently updated and homogenized 210 temperature and 461 precipitation locations, the presentation will show changes in a few indices related to drought, such as annual and summer mean of daily maximum temperature; number of days with maximum temperature > 30C (hot days); number of days with maximum temperature > 90th percentile (warm days), summer warm spells, the annual and summer total precipitation; rain to total precipitation ratio, days with rain; and number of consecutive dry days. The results will be presented for the periods 1900-2007 and 1950-2007 respectively.