Climate Change Chart of Jasper National Park, Canada

Overview of climate changes

Temperature changes

Averaged across calendar months, the difference in monthly mean temperature was +0.93 °C compared with the earlier reference period; this is an unweighted comparison of monthly means, not a day-weighted annual average or a measure of daytime maximum temperatures. The largest monthly increase was in January, with a difference of +3.92 °C. By contrast, October recorded the largest monthly decrease, a difference of -0.53 °C.

Changes in rainfall

Averaged across calendar months, mean daily rainfall had a difference of -0.12 mm/day compared with the earlier reference period. This summarizes monthly means and is not a day-weighted annual average or a monthly rainfall total. The largest monthly decrease was in June, where the difference was -0.93 mm/day. In September, the largest monthly increase was a difference of +0.21 mm/day; these extrema describe changes in mean daily amounts for those months.

Changes in snowfall

Averaged across calendar months, mean daily snowfall had a difference of +1.94 mm/day compared with the earlier reference period. This is an unweighted comparison of monthly means, not a day-weighted annual average or a monthly snowfall total. The largest monthly increase occurred in November, with a difference of +4.72 mm/day. The largest monthly decrease was in August, a difference of -0.48 mm/day; these monthly changes do not imply the same difference in every month.

Changes in sunshine duration

Mean daily sunshine duration, averaged across calendar months, had a difference of -0.40 hours/day compared with the earlier reference period. This is an unweighted summary of monthly means rather than a day-weighted annual average. February had the largest monthly decrease, with a difference of -0.72 hours/day in mean daily sunshine duration. This monthly extreme does not describe every month.