A General Introduction

In 2021, the average temperature of the county was much higher than that of the past years, and so was the sunshine duration, but the annual precipitation and rain days were close to those of the past years. In 2021, the main meteorological disasters were rainstorms, typhoons, strong convection, high temperatures, cold waves, etc.

A Description of Climate of Haiyan in 2021

Temperature: The average temperature of the year was 18.2℃, 1.1℃ higher than that of the past years, the highest on record. The average temperatures in August and November were close to those of the past years, but those in the other months were 0.7~3.7℃ higher. The average temperatures in February were 3.7℃ higher than those in February of the past years, the highest in average temperatures in the same period of the history of Haiyan. On July 14, the extreme maximum temperature reached 36.8℃ and the extreme minimum temperature fell to -6.7℃ on January 8. In the whole year, 10 days’ daily temperatures were equal to or higher than 35℃, but 20 days’ daily temperature were equal to or lower than 0℃.

Precipitation

The total precipitation reached 1429.7 mm in 2021, 42.0 mm more than that of the past years. In the whole year, ten days’ daily precipitation was equal to or more than 50 mm in 2021 and the precipitation distribution was extremely uneven. In May, July, August and September of the year, the monthly precipitation was more than that of the rest months, reaching 15.5~134.1 mm; abnormal precipitation occurred in July, 134.1 mm more than that of the past years. The precipitation in March was close to that of the past years, while that in the other months was 10.8 to 72.8 mm less than that of the past years. The precipitation in January of the year was 72.8 mm less than that of the past years.

The precipitation days totaled 148, 8.8 days more than those of the past years, and the precipitation days in January, February, April, September and December of 2021 were 1.3～6.3 days less than those of the past years. The precipitation days in January of the year were 6.3 days fewer than those of the past years, but the precipitation days in the rest months were all 1.2 ~ 6.0 days more that those of the past years, and the precipitation days in March of the year were 6.0 days more than those of the past years.

Sunshine duration

The sunshine duration totaled 2135.5 hours in 2021, 342.4 hours more than that of the past years, the second longest since the establishment of Meteorological Station of Haiyan. The sunshine duration in March, July and August of 2021 was 5.5 ~ 8.7 hours fewer than that of the past years and in August it was 8.7 hours fewer than that of the past years. It was 13.7 ~ 88.4 hours more in the rest months of 2021 than that of the past years, but it was 88.4 hours more in November of 2021 than that of the past years.