Trends in Canadian temperature and precipitation during the 20th century are analyzed using recently updated and adjusted station data. Six elements, maximum, minimum and mean temperatures along with diurnal temperature range (DTR), precipitation totals and ratio of snowfall to total precipitation are investigated. Anomalies from the IntroductionRecent analyses of climate trends indicate that the global mean surface temperature has increased by about 0.3 to 0.68C since the late 19th century, and by about 0.2 to 0.38C over the last 40 years (e.g., Nicholls et al., 1996). These studies have also shown that daily minimum temperatures have often increased at a greater rate than maximum temperatures, resulting in a decrease in the diurnal temperature range (DTR) for several regions of the world. There has been a small positive trend in global precipitation, of about 1% during the 20th century over land, with a greater increase in the high latitudes of the Northern Hemisphere, especially during the cold season. Considerable spatial and temporal variations have occurred over the past 100 years, and these tendencies of warming, increased precipitation and reduction of DTR have not been globally uniform. For example, Nicholls et al. (1996) showed warming in the mid-latitude Northern Hemisphere continents in winter and spring, and year-round cooling in the northwest North Atlantic and mid-latitudes over the North Pacific in the past four decades. Understanding the observed climate trends

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Four sets of geo-referenced grids of 1961-90 normals, or thirty-year

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