Why is the winter solstice at perihelion, summer solstice at perihelion, and at perihelion, the sun is closer to the earth, shouldn't it be hotter?

Because the earth's axis is inclined, the direct angle of the sun is different at different positions of the revolution, while it is winter in the perihelion in the northern hemisphere and summer in the southern hemisphere. Theoretically, the summer in the southern hemisphere is closer to the sun than that in the northern hemisphere, so the solar radiation in the southern hemisphere is slightly higher than that in the northern hemisphere.

In the whole four seasons, the most comfortable season is spring and autumn, because at this time the sun shines directly on the equator and the rain and dew in the north and south are wet! However, if there is no inclination of the earth's axis, the scope of the Arctic Circle and Antarctic Circle will expand, because it is still very cold in spring and autumn in high latitudes. If there is no balance in summer, perhaps most parts of Russia will live in harmony.

An important factor affecting the earth's access to radiant energy is the angle of sunlight, so how big is the influence of different angles? Under the direct condition, the ratio of the cross-sectional area of sunlight to the area of ground radiation is 1: 1.