Recently, Beijing-Tianjin-Hebei ushered in a wide range of cold wave cooling weather. What is the main force?

Recently, the Beijing-Tianjin-Hebei region will usher in a wide range of cold wave cooling weather, mainly caused by cold air. Cold air refers to the air mass with low temperature and humidity, which flows in from the north or northwest, resulting in a sharp drop in temperature. In this cold wave cooling weather, Beijing, Tianjin and Hebei will be widely affected by cold air, resulting in a significant drop in temperature. According to the forecast, the temperature drop in North China, Huanghuai and other places is relatively large. The lowest temperature 0℃ line will be pressed south to the south of Shandong Peninsula, south of Hebei Province to the middle of Shanxi Province, and the lowest temperature-10℃ line will be pressed south to the middle of Hebei Province and the north of Shandong Peninsula. The arrival of cold air will bring cold weather conditions and bring a series of challenges and influences to people's life, transportation and agriculture. People should take corresponding cold-proof measures, strengthen heating and add clothes. To ensure their health. Farmers should also take protective measures to reduce the adverse effects of cold wave on crops. Cold air brings pressure to energy supply and urban heating, and corresponding countermeasures should be strengthened.