Climate Change Chart of Jackson, USA

Overview of climate changes

Temperature changes

Averaged across calendar months, monthly mean temperature shows a difference of +0.55 °C compared with the earlier reference period; this is an unweighted comparison of monthly means, not a day-weighted annual average or a statement about daytime maximum temperatures. The largest monthly increase was in December, at a difference of +1.40 °C. By contrast, November had the largest monthly decrease, with a difference of -0.25 °C. These month-specific differences show that the overall mean masks variation between calendar months, rather than indicating that every month changed in the same direction.

Changes in rainfall

Mean daily rainfall was higher on average across calendar months in the more recent period, with a difference of +0.64 mm/day; this unweighted mean across monthly means is not a monthly total or a day-weighted annual average. The largest monthly increase occurred in August, at a difference of +2.07 mm/day, while March recorded the largest decrease, a difference of -0.27 mm/day. These contrasting monthly changes qualify the overall mean: it summarizes the calendar-month averages and does not imply that daily rainfall increased in every month or on every day.

Changes in sunshine duration

Mean daily sunshine duration averaged across calendar months had a difference of -0.03 hours/day compared with the earlier reference period; this is an unweighted comparison of monthly means, not a day-weighted annual figure. Monthly differences varied in direction: September had the largest increase, at a difference of +0.60 hours/day, whereas August had the largest decrease, at a difference of -0.77 hours/day. The mean therefore provides a broad summary, while the month-specific results show why it should not be read as a uniform change throughout the calendar year.

Changes in snowfall

Mean daily snowfall averaged across calendar months had a difference of -0.04 mm/day in the more recent period. This unweighted comparison of monthly means is not a monthly snowfall total or a day-weighted annual average, and the small difference should be understood at the precision displayed rather than as evidence that snowfall was absent. The largest monthly decrease was in January, with a difference of -0.25 mm/day; February had the largest increase, at a difference of +0.01 mm/day. The monthly contrasts show that the overall mean does not describe the direction of change in every calendar month.