Which is better for people's health, cloudy or sunny?

Cloudy weather is different from cloudy weather.

Cloudy weather can be divided into two types. The first is the kind of weather with blue sky and white clouds in full bloom and the sun shining. At this time, the atmospheric pressure is low, the clouds stay in the troposphere, the water vapor content in the air is high, and the negative ion concentration is high. Studies have proved that negative ions in the air are conducive to improving people's thinking agility; In addition, the thick clouds block the direct sunlight and prevent ultraviolet rays from harming people. Therefore, this cloudy weather is an ideal weather for people's health.

Another kind of cloudy weather is the kind that seems to be sunny at first glance, but the upper part of the sky is completely covered by a thin layer of clouds. This is caused by the rise of clouds such as altocumulus and stratocumulus in the stratosphere. At this time, the atmospheric pressure is high, the water in the air is thin and the atmospheric circulation is not enough. If it appears in the alternation of seasons, it is easy to cause the onset of respiratory diseases in susceptible people. In addition, because the clouds are too thin, the resistance to ultraviolet rays is far from as good as people think, and long-term outdoor work may be burned. Therefore, this cloudy day is not good weather.

Sunny days generally have no adverse effects on people, but when sunny days are too hot, outdoor work should be minimized to avoid heatstroke and ultraviolet burns.