Northwest wind blows during the day and southeast wind blows at night. The heat capacity of seawater is greater than that of land. During the day, the temperature of seawater rises slowly, and the temperature and air pressure on land are high. The wind blowing from land to sea is northwest wind, but it is the opposite at night.

Because the heat of land soil is much less than that of sea water, the temperature of land is much faster than that of ocean, and the temperature of inland land capacity is obviously higher than that of nearby ocean. Under the action of horizontal pressure gradient force, the air above flows from land to sea, then sinks to low altitude, then flows from sea surface to land, and rises again, thus forming low-level sea breeze and sea breeze circulation on vertical section.

Extended data:

Climatic characteristics of coastal areas:

1, mild coastal climate

Coastal climate is also called marine climate. The driving force of climate formation on the earth comes from the radiant energy of the sun. Because of its inherent characteristics, the ocean has formed a climate obviously different from that on land.

2. Fresh sea-land breeze circulation

People who live by the sea will feel that the wind direction changes regularly during the day and night. After sunrise during the day, there is a cool breeze blowing from the sea to the land, bringing fresh air, especially in hot summer and summer. The cool sea breeze blows on the face, which makes people feel refreshed and exhausted. When night comes, the wind turns from land to water, sending away the dirty air.

3. Sunny and soft beach.

There is plenty of sunshine in the coastal areas of China. Even in rainy season, the sunshine percentage is around 50%. In addition, the winding coastline of China is a sandy structure, which forms many natural sunshine and bathing beaches. Coupled with bright sunshine, vast horizon, blue sky, soaring seabirds and endless periodic waves, it will have a good psychological and physiological impact on people.