Climate Change Chart of Lausanne, Switzerland

Overview of climate changes

Temperature changes

Averaged across calendar months, monthly mean temperatures show a difference of +1.49 °C in the more recent period; this is an unweighted comparison of the 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 +3.30 °C compared with the earlier reference period. By contrast, May had the largest monthly decrease, a difference of -0.03 °C.

Changes in rainfall

Mean daily rainfall averaged across calendar months had a difference of +1.47 mm/day in the more recent period. This unweighted mean describes the aggregate of monthly means, rather than a day-weighted annual average, and the values refer to daily averages rather than monthly rainfall totals. The largest monthly increase in mean daily rainfall occurred in July, with a difference of +2.21 mm/day compared with the earlier reference period. That identifies the strongest monthly increase in the supplied comparison, not a change shared by every month.

Changes in sunshine duration

Averaged across calendar months, mean daily sunshine duration had a difference of -0.32 hours/day in the more recent period. This is an unweighted comparison of monthly means, not a day-weighted annual average. The largest monthly decrease was in December, where mean daily sunshine duration had a difference of -0.63 hours/day compared with the earlier reference period. This monthly result should not be read as applying to every month.

Changes in snowfall

The unweighted mean of monthly mean daily snowfall across calendar months had a difference of 0.00 mm/day at the displayed precision. The rounded equality does not establish that snowfall was absent or that every month's value was unchanged; these are daily means, not monthly totals. Monthly snowfall differences varied: March recorded the largest increase, a difference of +1.39 mm/day, while January recorded the largest decrease, a difference of -1.58 mm/day compared with the earlier reference period.