Climate Change Chart of Lucerne, Switzerland

Overview of climate changes

Temperature changes

Averaged across calendar months, monthly mean temperature shows a difference of +1.71 °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 January, with a difference of +4.00 °C. This identifies the strongest increase among the supplied monthly comparisons, rather than implying that every month changed by the same amount.

Changes in rainfall

Mean daily rainfall, averaged across calendar months, had a difference of +1.08 mm/day in the more recent period. This unweighted comparison of monthly means describes an aggregate, not a day-weighted annual average, and the values are daily amounts rather than monthly totals. The largest monthly increase in mean daily rainfall occurred in July, with a difference of +2.29 mm/day. It marks the most pronounced increase among the supplied months; it does not describe rainfall on every day in that month.

Changes in sunshine duration

Mean daily sunshine duration, averaged across calendar months, had a difference of -0.66 hours/day compared with the earlier reference period. This unweighted mean summarizes monthly averages rather than a day-weighted annual total, and does not mean that sunshine changed by the same amount in every month. The largest monthly decrease in mean daily sunshine duration was in March, with a difference of -0.88 hours/day. This points to the strongest monthly decrease in the supplied comparison, not a uniform change across days.

Changes in snowfall

Averaged across calendar months, mean daily snowfall had a difference of -0.89 mm/day in the more recent period. This is an unweighted mean of monthly averages, not a day-weighted annual average; it describes the overall comparison without implying the same change in each month. The largest monthly decrease in mean daily snowfall was in February, with a difference of -2.65 mm/day. By contrast, the largest monthly increase occurred in April, with a difference of +1.86 mm/day. These contrasting monthly differences show why the across-month mean should not be read as a description of every month; the figures are daily means, not monthly snowfall totals.