On the Hydrological Characteristics of Henan Province

Henan is located in the middle and east of China, in the middle and lower reaches of the Yellow River, between 3123'-36 22' north latitude, and10 21'16 39' east longitude, with Anhui and Shandong in the east. Henan is located in the middle of China, connecting the east with the west. Known as Heaven and Earth in ancient times, it is regarded as the world hub where China is located.

Henan Province is high in the west and low in the east. Taihang Mountain, Funiu Mountain, Tongbai Mountain and Dabie Mountain are distributed in three directions along the provincial boundary in a semicircle. The central and eastern parts are the Huanghuaihai Plain; Nanyang basin is in the southwest.

The plains and basins, mountains and hills in Henan Province account for 55.7%, 26.6% and 17.7% of the total area respectively. Laoya tea in lingbao city is the highest peak in the province, with an altitude of 2413.8m; The lowest is the exit of Huaihe River in Gushi County, only 23.2 meters.

Henan has a warm temperate-subtropical, humid-semi-humid monsoon climate. Generally speaking, there is less rain and snow in winter, more wind and sand in spring, plenty of hot water in summer and sunny autumn. The average annual temperature in the whole province is generally between 12℃- 16℃, 1 month between -3℃-3℃, and July between 24℃-29℃, which is generally high in the east and low in the west, high in the south and low in the north, with obvious differences between mountainous areas and plains. The diurnal range of annual range is large, and the extreme minimum temperature is-2 1 .7℃ (1951year1month 12, Anyang). The extreme maximum temperature is 44.2℃ (1June 20th, 966, Luoyang). The frost-free period of the whole year is 180-240 days from north to south. The average annual precipitation is about 500-900 mm, with more mountains in the south and west, and the Dabie Mountains can reach more than1100 mm. 50% of the annual precipitation is concentrated in summer, and there are often heavy rains.

Henan is not only the largest agricultural province, the largest grain production province and the largest grain conversion and processing province in China, but also an important economic province and a rapidly developing new industrial province.