This map shows the median date of snow-cover loss (defined as the last date with 14 consecutive days of snow cover greater than 2 centimetres in depth) computed over 18 winter seasons (1979 to 1997). In areas with permanent or semipermanent snow cover (for example, Arctic ice caps) or in areas with irregular or ephemeral snow cover (coastal British Columbia), researchers were unable to compute the median values. The end date contours follow topography more closely than start date due to the influence of elevation on total snow accumulation and air temperature. The date of snow-cover loss has important implications for wildlife (for example, bird migration and nesting), vegetation, local climate and hydrology.