The geographical environment of Jinniu District

Rizhao: The average annual sunshine hours in Jinniu District is 1,238 hours, with the maximum annual sunshine hours being 1,461 hours and the minimum annual sunshine hours being 827 hours. The average annual sunshine percentage is 26%, with the highest year being 33% and the lowest year being 19%. The seasonal changes in sunshine hours and sunshine percentage are basically the same, with the highest in summer (June to August), the lowest in winter (December to February), and greater in spring than in autumn. The average total solar radiation is 3718.5 MJ/m2, with the maximum year being 4089 MJ/m2 and the minimum year being 3031.9 MJ/m2. The total radiation amount is the largest in summer, accounting for about 40% of the total annual radiation amount. The maximum value occurs in July, which is 465.22 MJ/m2; the radiation amount is the least in winter, accounting for 14% of the total annual radiation amount; the minimum value occurs In December; the amount of radiation in spring is greater than in autumn.

Temperature: Jinniu District belongs to the subtropical temperate climate zone of the Sichuan Basin, with an average annual temperature of 16.2°C and an accumulated temperature of 5937°C. The highest temperature was 40.1°C (July 4, 1941), and the lowest temperature was -6°C (January 5, 1955). January has the lowest temperature, with an average of 5.3°C to 6.1°C. The average number of days with the highest sunshine temperature greater than or equal to 30.0°C was 49 days in 2012, which mainly occurred from mid-July to mid-August. Throughout the year, the maximum daily temperature greater than or equal to 30.O℃ begins in mid-April at the earliest and ends in late September at the latest. Weather with the daily maximum temperature greater than or equal to 35.0℃ is rare; the number of days with the daily minimum temperature below or equal to 0.0℃ averages about 12 days per year, which occurs from late November to mid-March, and most of them occur from late December to mid-March. Between early February.

Precipitation: The average annual precipitation in Jinniu District is 940.0 to 1034.6 mm. Due to the influence of terrain and urban industrial areas, the east has more precipitation than the west. Shahebao in Baohe Township has the most precipitation, and Cuqiao has the most precipitation. Township is the least.

Precipitation in each season within the territory: Winter precipitation is roughly between 22 and 24 mm, with very small regional differences. The precipitation in spring is 150-160 mm, 5-7 times more than in winter. It is 160 mm in the surrounding suburbs and decreases toward the surrounding areas - less than 155 mm in Wenjia, Cuqiao, Sansheng, and Tianhui, and about 150 mm in the eastern part of Longtan Township. Summer is the season with the most precipitation in 2012, and it determines to a large extent the distribution characteristics of annual precipitation: 575 to 660 mm in Jinniu District; more in the east and less in the west - more than 600 mm in Qinglong Township, Guixi Township and the east areas Millimeters; Shahebao has the most, reaching 663 millimeters; Cuqiao Township in the southwest has less than 580 millimeters; Tianhui Township in the north has less than 590 millimeters. The autumn precipitation is 180-210 mm; it decreases from northwest to southeast - 200-210 mm in Wenjia, Jinniu, Heping and other townships; 180 mm in the eastern part of Longtan Township, Sansheng Township and the southern part of Shiyangchang Township. According to records from 1951 to 1985: the number of days with daily rainfall ≥0.1 mm, and the annual average of 149 days. July has the most days, with 17.2 days, accounting for 55% of the number of days in the month; followed by September, with 16.2 days; December has the least, with only 6 days.

The number of days with daily rainfall ≥25 mm, with an annual average of 9.4 days, occurs from April to October, with the most days in July and August, with a maximum of 6.1 days, accounting for 65% of the total in 2012.

The number of days with daily rainfall ≥50 mm, with an annual average of 2.9 days, occurs from April to September, with July and August being the most common, accounting for 77% of the total in 2012.

The number of days with daily rainfall ≥100 mm, with an annual average of 0.4 days, mainly occurs in July and August. Nighttime precipitation is more than twice that of daytime precipitation. The ratio of night to day precipitation is greater in spring and autumn than in winter and summer. According to records from 1954 to 1985, the annual average number of night rain days is 127.7 days, and the number of day rain days is 94.1 days. Except for December and January, the number of night rain days is more than the number of day rain days in each month.

The precipitation intensity is the highest in summer, with the maximum daily precipitation of 201.3 mm (July 13, 1981). From December to February of the following year, the daily precipitation is less than 10 mm. The maximum precipitation in one hour can reach 67.5 mm (May 22, 1954), which mostly occurs at night from April to September. The maximum precipitation in ten minutes was 24.1 mm (July 24, 1961). It mostly occurs during the day in summer and at night in other seasons.

The longest number of consecutive days with precipitation and no precipitation. According to records from 1951 to 1985, the longest number of consecutive days with precipitation is 19 days. There are fewer consecutive precipitation days in winter. The precipitation in July and August in summer is heavy and lasts for a long time, making floods prone to occur. The number of consecutive days without precipitation in 2012: 3 to 5 days in December, 3 to 9 days in January, 3 to 8 days in February, and 11 to 12 days in June to September.

Air humidity: The relative humidity is 77% to 86% in all months throughout the year, with the highest in autumn, followed by summer, and the smallest in spring. The annual average relative humidity is 82%, and the eastern suburbs are 1% to 3% lower than the western suburbs.

Frost period: According to the average number of frost days in each month and the dates of first and last frost from 1951 to 1985, the average number of frost days per year is 20.5 days, with the maximum number of years being 41 days and the minimum number being 10 days. Most frost days occur from November to April of the following year, with the most frost days in January, with an average of 9.6 days. The first frost period is generally in December, the earliest is early November, the latest is late December, the earliest is the end of January, and the latest is the end of March.

The longest frost period is 128 days, the shortest is 51 days, and the average frost-free period is 279 days. Few frost days, short frost period, long frost-free period, and not cold winter are the characteristics of the winter climate in this area.