<P> Owing to tremendous differences in latitude, longitude, and altitude, the climate of China is extremely diverse, ranging from tropical in the far south to subarctic in the far north and alpine in the higher elevations of the Tibetan Plateau . Monsoon winds, caused by differences in the heat - absorbing capacity of the continent and the ocean, dominate the climate . During the summer, the East Asian Monsoon carries warm and moist air from the south and delivers the vast majority of the annual precipitation in much of the country . Conversely, the Siberian anticyclone dominates during winter, bringing cold and comparatively dry conditions . The advance and retreat of the monsoons account in large degree for the timing of the rainy season throughout the country . Although most of the country lies in the temperate belt, its climatic patterns are complex . </P> <P> The northern extremities of both Heilongjiang and Inner Mongolia have a subarctic climate; in contrast, most of Hainan Island and parts of the extreme southern fringes of Yunnan have a tropical climate . Temperature differences in winter are considerable, but in summer the variance is considerably less . For example, Mohe County, Heilongjiang has a 24 - hour average temperature in January approaching − 30 ° C (− 22 ° F), while the corresponding figure in July exceeds 18 ° C (64 ° F). By contrast, most of Hainan has a January mean in excess of 17 ° C (63 ° F), while the July mean there is generally above 28 ° C (82 ° F). </P> <P> Precipitation is almost invariably concentrated in the warmer months, though annual totals range from less than 20 millimetres (0.8 in) in northwestern Qinghai and the Turpan Depression of Xinjiang to easily exceeding 2,000 millimetres (79 in) in Guangdong, Guangxi, and Hainan . Only in some pockets of the Dzungaria region of Xinjiang is the conspicuous seasonal variation in precipitation that defines Chinese (and, to a large extent, East Asian) climate absent . </P> <P> Annual sunshine duration ranges from less than 1,100 hours in parts of Sichuan and Chongqing to over 3,400 hours in northwestern Qinghai . Seasonal patterns in sunshine vary considerably by region, but overall, the north and the Tibetan Plateau are sunnier than the south of the country . </P>

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