Climate Change Chart of Hagåtña, Guam

Overview of climate changes

Changes in rainfall

Averaged across calendar months, mean daily rainfall increased by +2.57 mm/day compared with the earlier reference period. This is an unweighted mean of monthly daily averages, not a day-weighted annual average or a monthly rainfall total, and it does not imply that rainfall increased in every month. The largest monthly increase in mean daily rainfall occurred in October, with a difference/change of +7.93 mm/day. By contrast, December had the largest monthly decrease, a difference/change of -1.17 mm/day. These are changes in daily averages for those months, not monthly totals.

Changes in sunshine duration

Averaged across calendar months, mean daily sunshine duration shows a difference/change of -0.66 hours/day compared with the earlier reference period. This unweighted mean summarizes the monthly daily averages; it does not indicate that sunshine duration fell in every month. The largest monthly decrease in mean daily sunshine duration was in October, with a difference/change of -1.92 hours/day. In December, the largest monthly increase was a difference/change of +0.22 hours/day, showing that the monthly differences were not uniform in direction.

Temperature changes

Averaged across calendar months, monthly mean temperature shows a difference/change of +0.52 °C compared with the earlier reference period. This is an unweighted comparison of the monthly means, not a day-weighted annual average, and it describes the overall average difference rather than a change in every month. The largest monthly increase in mean temperature was in May, with a difference/change of +0.93 °C. This identifies the strongest monthly increase in the supplied comparison; it does not mean daytime maximum temperatures rose by the same amount.