Why is the air pressure higher in winter than in summer and higher in sunny days than in cloudy days?

1, low temperature leads to high air pressure. Because cold air is heavy and sinks, while hot air rises. It is obviously hot in Leng Xia in winter, so the air pressure in winter is higher than that in summer, and there are clouds on cloudy days, which will hinder the heat dissipation near the ground and increase the temperature near the ground. There are no thick clouds on sunny days, which makes the ground radiate heat while receiving solar radiation, thus reducing the temperature near the ground. So the air pressure on sunny days is greater than that on cloudy days. (the above content will be learned in senior one geography. 2. An object immersed in a liquid is subjected to upward buoyancy, and the buoyancy is equal to the gravity of the liquid displaced by the object. In layman's terms, it is because an object floats in water, is static and is acted by a pair of balancing forces, so this pair of balancing forces is the downward gravity of the earth and the upward buoyancy of the water. Then, buoyancy is of course equal to gravity. 3. Mercury in the tube and the atmosphere outside the tube, the pressure of the atmosphere on the mercury surface in the mercury tank is equal to the pressure of the mercury surface in the tube and the mercury surface in the mercury tank, and the pressure in the tube is generated by the mercury column in the tube, so the mercury column pressure in the tube is equal to the atmospheric pressure. In other words, a small cross section at the bottom of the liquid column is taken as the research object, which is subjected to the downward pressure of the upper liquid column and the upward pressure of the lower liquid, so these two forces are balanced, so P atmospheric pressure =P mercury = ρ mercury * g * H. I am a senior two student in Zhengzhou No.1 Middle School, and the above contents are summarized by myself. If you don't understand anything, just keep asking ~)