Climate Change Chart of Kirkwood, USA

Overview of climate changes

Temperature changes

Monthly mean temperature was higher by an averaged-across-calendar-months difference of +0.85 °C in the more recent period; this is an unweighted comparison of monthly means, not a day-weighted annual average or a measure of daytime maximum temperatures. The largest monthly increase was in December, with a difference of +2.04 °C compared with the earlier reference period. The largest monthly decreases were shared by August / October, each with a difference of -0.35 °C. These selected monthly differences describe particular months and do not imply that every month changed in the same direction.

Changes in rainfall

Mean daily rainfall increased by an averaged-across-calendar-months difference of +0.81 mm/day in the more recent period. This unweighted mean compares calendar-month averages; it is not a monthly rainfall total or a day-weighted annual average. The largest monthly increase was in July, where mean daily rainfall showed a difference of +3.09 mm/day compared with the earlier reference period. By contrast, November had the largest monthly decrease, with a difference of -0.09 mm/day; these monthly differences do not describe daily variability.

Changes in sunshine duration

Mean daily sunshine duration had an averaged-across-calendar-months difference of -0.34 hours/day in the more recent period, indicating a lower mean across the calendar-month averages rather than a day-weighted annual figure. The largest monthly decrease was in October, with a difference of -0.96 hours/day. The largest monthly increase occurred in September, at a difference of +0.17 hours/day, so the overall mean difference does not mean sunshine moved in the same direction in every month.

Changes in snowfall

Mean daily snowfall had an averaged-across-calendar-months difference of -0.20 mm/day in the more recent period. This is an unweighted comparison of calendar-month means, not a monthly total; the aggregate does not describe every month's change. The largest monthly decrease was in March, with a difference of -1.70 mm/day, while November had the largest monthly increase, at a difference of +0.35 mm/day. These daily-mean comparisons show contrasting monthly differences and do not establish how snowfall varied from day to day.