Hainan Island is separated from Qiongzhou Strait in the north and faces Leizhou Peninsula. Qiongzhou Strait, about 30 kilometers wide, is a maritime "corridor" between Hainan Island and Chinese mainland, and also a shipping channel between Beibu Gulf and South China Sea.
The annual average temperature in Hainan is 22.5 ~ 25.6℃, with the lowest in Qiongzhong in the middle and the highest in Sanya in the south. The isotherm is distributed in an arc to the south, increasing from the central mountainous area to the surrounding coastal areas, and the isotherm at 23℃ is closed in the central mountainous area. Due to the adjustment of the ocean, the annual variation of temperature in Hainan is generally small, ranging from 8 ~ 10℃ in most areas, and the smallest in Sanya (7.6℃). Generally 5 ~ 10℃ lower than that in Chinese mainland.
Extended data
The climate of Hainan Island
Hainan Island is located in the south of the Tropic of Cancer, with a high sun angle all year round. The sun is located at the zenith twice in summer, and the altitude angle of the sun at noon is 84 45 ′ ~ 86 45 ′. Even on the winter solstice, the noon sun altitude angle is 46 05 ′ ~ 48 05 ′. There is almost no difference between summer solstice and winter solstice.
The solar radiation energy is quite rich and there is plenty of sunshine. The annual total solar radiation is 4600 ~ 5800 MJ/m2 and the annual sunshine hours 1793 ~ 2590 hours, which lays the foundation for the formation of tropical climate. Hainan Island is located in the East Asian monsoon region, which is obviously influenced by the monsoon. Both easterly belt system and westerly belt system have influence on it.
Baidu Encyclopedia-Hainan Island