Climate Change Chart of Ny-Ålesund, Norway

Overview of climate changes

Temperature changes

Averaged across calendar months, monthly mean temperature shows a difference of +3.07 °C compared with the earlier reference period; this is an unweighted mean of monthly means, not a day-weighted annual average or a measure of daytime maximum temperatures. The largest monthly increase was in February, with a difference of +5.95 °C. This identifies the strongest increase among the monthly means, not a change shared by every month.

Changes in snowfall

Averaged across calendar months, mean daily snowfall had a difference of -1.31 mm/day compared with the earlier reference period. This is an unweighted mean of monthly means, not a day-weighted annual average, and refers to daily amounts rather than monthly totals. Monthly snowfall differences varied: the largest decrease occurred in December, with a difference of -5.84 mm/day, while the largest increase was in February, with a difference of +2.29 mm/day. These are monthly mean daily amounts and do not mean the same direction applied across all months.

Changes in sunshine duration

Mean daily sunshine duration, averaged across calendar months, had a difference of -1.07 hours/day compared with the earlier reference period. This unweighted mean of monthly means is not a day-weighted annual average, and the aggregate difference does not describe every month. The largest monthly decrease was in June, with a difference of -4.24 hours/day in mean daily sunshine duration. By contrast, February recorded the largest monthly increase, a difference of +0.08 hours/day; these extrema show that monthly differences were not uniform.

Changes in rainfall

Averaged across calendar months, mean daily rainfall had a difference of +0.23 mm/day compared with the earlier reference period. This is an unweighted average of monthly means, rather than a day-weighted annual average, and describes daily amounts rather than monthly rainfall totals. The largest monthly increase in mean daily rainfall occurred in September, with a difference of +0.79 mm/day; that monthly result does not imply the same change in other months.