It's raining.

The sultry weather is closely related to the air pressure. Generally speaking, areas with high ground pressure are often sunny, and areas with low ground pressure are often rainy. The high pressure and low pressure mentioned here are relative, not the absolute value of atmospheric pressure.

The air pressure in a certain area is higher than the surrounding air pressure, which is called high pressure area; The air pressure in a certain area is lower than the surrounding air pressure, which is called low pressure area. On the same horizontal plane, if the air pressure distribution is uneven, the air will flow from the high pressure area to the low pressure area. Therefore, the air pressure in a certain area is high, and the air in this area flows out in the horizontal direction.

The air above the high pressure area will drop. Because the atmospheric pressure increases with the decrease of altitude, when the air at high altitude falls, the pressure is increased, the volume is decreased, the temperature is increased, and the condensate in the air evaporates and dissipates.

Therefore, the high-pressure central area is not conducive to the formation of clouds and rain, and it is often sunny. If the air pressure in a certain area is low, the air in the surrounding area will flow into the area horizontally, causing the air in the area to rise, the rising air will expand due to the pressure drop, the temperature will drop, and the water vapor in the air will condense. Therefore, it often rains in the central area of low pressure.

Extended data:

Attention should be paid to sultry weather:

1, in hot summer, the diet should be light; Drink more boiled water and replenish water in time, which can supplement the blood volume deficiency caused by a lot of sweating and reduce the blood viscosity; Quit smoking and limit alcohol, and eat more fruits and vegetables; Avoid eating too cold food, which will increase the gastrointestinal burden and induce myocardial infarction.

2, keep enough sleep, work and life should be combined with relaxation; Control emotions, relieve stress in time and avoid mental stress; The indoor air conditioning temperature should not be too low, and should be kept at about 26 degrees Celsius to avoid sudden contraction of blood vessels caused by cold and heat and cardiovascular accidents.

3, regular exercise, avoid strenuous exercise, especially in patients with coronary atherosclerosis stenosis, in order to prevent the original myocardial blood supply from aggravating, leading to myocardial infarction.

People's Daily Online-Attention should be paid to preventing myocardial infarction in hot weather.

Baidu encyclopedia-sultry weather

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