Why is it getting colder and colder?

Recently, northern China is experiencing a "cold spring".

The late spring cold in meteorology refers to the phenomenon that it is warm in the early spring, cold in the late spring, and the temperature in the late spring is obviously lower than normal. The word "inverted" in the cold spring is reflected in the warmth before and the coolness after.

Due to the different phenology in the north and south of China, the time of cold in spring is different in different places. Generally speaking, the temperature rises quickly in the south, and spring comes early, early and late in the north. Generally speaking, it occurs in April-May in the north and in March-May in the south.

Related information:

Spring is the transitional period of winter wind direction and summer monsoon in China, during which intermittent cold air often comes from the northwest. The cold air goes south and sticks to the warm and humid air in the south, and the temperature fluctuates greatly. When the cold air goes south late, the intensity is large, and the cooling range is wide, it is more likely that there will be a large-scale late spring cold.

China, Japan, North Korea, India and the United States all experienced a cold spring.