Climate Change Chart of Stockholm, Sweden

Overview of climate changes

Temperature changes

Averaged across calendar months, monthly mean temperature shows a difference of +1.51 °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 highs. The largest monthly increase was in January, with a difference of +3.65 °C. That month-specific contrast sits alongside the overall mean and does not imply that every month warmed by the same amount.

Changes in snowfall

Mean daily snowfall averaged across calendar months shows a difference of -0.34 mm/day in the more recent reference period, an unweighted comparison of monthly means rather than monthly totals. The largest monthly decrease was in December, with a difference of -1.38 mm/day; by contrast, May had the largest increase, with a difference of +0.37 mm/day. These contrasting month-specific differences help explain why the aggregate mean should not be treated as a uniform change throughout the calendar year. Daily means also do not describe how snowfall varied from day to day.

Changes in rainfall

Mean daily rainfall averaged across calendar months shows a difference of +0.25 mm/day in the more recent period, an unweighted mean of monthly conditions rather than a comparison of monthly totals. The largest monthly increase occurred in October, with a difference of +0.80 mm/day. In contrast, April had the largest monthly decrease, a difference of -0.25 mm/day. These monthly differences show that the aggregate increase does not describe every month's direction, and daily means do not indicate how rainfall was distributed from day to day.

Changes in sunshine duration

Mean daily sunshine duration, averaged across calendar months, had a difference of -0.02 hours/day compared with the earlier period; the figure is an unweighted comparison of monthly means, not a day-weighted annual measure. The month-to-month contrasts were more pronounced in opposite directions: April recorded the largest increase, with a difference of +0.89 hours/day, while October recorded the largest decrease, with a difference of -0.73 hours/day. The small overall mean difference therefore should not be read as an identical change in each month or as a description of daily variability.