Influence of China's topography and climate on river course, water quantity and other characteristics

The terrain of China is three steps. The first step, with the advantage of altitude, the top of the mountain is extremely cold, the temperature is low, there are many mountains, the ice and snow melt, and the mountain precipitation. Rivers freeze in winter, and there are flood seasons in spring and summer. Because the temperature rises in spring and the snow melts, the summer is generally high all over the country. The first step is the birthplace of many rivers in China. Due to high altitude, thin air, large temperature difference between day and night and strong wind, the steps high in the west and low in the east have created rivers. The same is true for the second and third steps. The third level is low-lying, close to the sea, with humid air flow from the ocean, and the climate is warm and humid. The central part is relatively dry, but the area located in the basin is like spring all the year round, such as Kunming in Sichuan Basin. The ice age of rivers is in winter and spring, and only rivers in the north will freeze, such as Songhua River, Heilongjiang River and Pearl River. Climate includes temperature and precipitation. Temperature affects the ice age of rivers, and precipitation affects it.