Climate Change Chart of St. Gallen, Switzerland

Overview of climate changes

Temperature changes

Averaged across calendar months, monthly mean temperature shows a difference of +1.97 °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 +5.18 °C. By contrast, May had the largest monthly decrease, a difference of -0.09 °C, showing that the overall mean change did not apply equally in every month.

Changes in snowfall

Mean daily snowfall averaged across calendar months had a difference of +0.11 mm/day compared with the earlier reference period, an unweighted average of monthly means rather than a day-weighted annual figure or monthly total. The largest monthly increase occurred in April, with a difference of +3.33 mm/day. In February, the largest monthly decrease was a difference of -1.40 mm/day. These contrasting monthly changes show why the average across months should not be taken to describe every month.

Changes in rainfall

Mean daily rainfall, averaged across calendar months, had a difference of +0.88 mm/day compared with the earlier reference period. This is an unweighted average of monthly means, not a day-weighted annual figure or a monthly rainfall total. The largest monthly increase occurred in August, where mean daily rainfall had a difference of +1.94 mm/day; that monthly contrast is distinct from the across-month average.

Changes in sunshine duration

Mean daily sunshine duration averaged across calendar months had a difference of -0.37 hours/day compared with the earlier reference period. This unweighted summary of monthly means does not describe every month individually. The largest monthly decrease was in May, with a difference of -0.59 hours/day in mean daily sunshine duration.