How many degrees does hot weather mean?

Lead: Hot weather has a great influence on people. When you work outdoors, you should take effective protective measures. Recently, some friends want to know, what is the high temperature? How many degrees of high temperature can the human body withstand? I've compiled some necessary information for you here. I hope you can learn useful knowledge from it.

How many degrees does hot weather mean?

Refers to more than 35 degrees, and high temperature weather refers to the weather phenomenon that the daily maximum temperature reaches or exceeds 35 degrees; A high-temperature weather process that lasts for several days (more than three days) is called high-temperature heat wave (or high-temperature heat wave).

Generally speaking, there are usually two kinds of high temperature, one is dry heat and high temperature with high temperature and low humidity; The other is hot and humid, which is called "sauna day".

High temperature warning signal

The high temperature warning signal is divided into three levels, which are represented by yellow, orange and red respectively.

1, the standard of high temperature yellow warning signal is: the daily maximum temperature is above 35℃ for three consecutive days,

2. The standard of high temperature orange warning signal is that the maximum temperature rises above 37℃ within 24 hours.

3. The standard of high temperature red warning signal is that the maximum temperature rises above 40℃ within 24 hours.

In China, except for some areas such as the Qinghai-Tibet Plateau, high temperature weather occurred in almost all places, including Mohe in the northernmost part (five high temperature weather occurred in June of 20 10). The high temperature weather in China is mainly concentrated in May -65438+ 10.

High temperature weather, the main impact on human health is heatstroke and cardiovascular and cerebrovascular diseases leading to death.

How many degrees of high temperature can the human body withstand?

Scientifically speaking, the natural temperature of the human body is 37 degrees Celsius. As a miracle of natural evolution, the human body has a very high ability to control heat. When the weather is hot, the human body can use perspiration to dissipate heat, but there is a limit temperature in this way, which is 35 degrees Celsius. Once the temperature reaches or exceeds 35 degrees Celsius, the human body can no longer sweat, because the air is full of evaporated water vapor. Even if sweat flows out, it can't dissipate heat through evaporation.

This may scare us, because the temperature of 35 degrees Celsius is no longer rare in today's summer. It is roughly estimated that there are ten days when we meet above 35 degrees Celsius in a summer. In the Mediterranean, Canada and India, human beings are worried about unprecedented high temperatures. Scientists believe that once the extreme high temperature in summer in these places becomes the norm, it will no longer be suitable for human habitation, at least in summer.

This is too difficult for ordinary people. It is impossible for ordinary people to leave their city and go to a cool place to cool off in hot weather. Ever since, in these cities, ordinary migrant workers still need to work under the scorching sun, especially for takeaway and courier brothers, every summer is a test.

Air temperature ≠ somatosensory temperature

Why is the temperature felt when walking in the street on a hot day higher than the actual temperature announced by the meteorological department?

Somatosensory temperature is actually a feeling that people get physically or mentally when they come into contact with the external environment through the skin. Under the same temperature conditions, people will have different cold and warm feelings due to differences in humidity, wind speed, solar radiation (or solar radiation), dress color and even mood. For example, when the humidity is high, it will cause discomfort such as joint pain; When the wind is strong, it will promote heat loss; When the sunshine is low, the human body will feel colder.

The actual temperature refers to the temperature measured in the ground 1.5-meter-high shutter box. Temperature measurement must be carried out in a relatively open place, with the thermometer at a distance of 1.5 meters from the ground and placed in a louver box to avoid direct sunlight. This is a unified standard formulated by the Global Meteorological Organization. The temperature measured in this way is the temperature mentioned in meteorology, that is, the air temperature in the natural state.

It is observed that under normal circumstances, the temperature of concrete floor is 4℃ higher than that of louvers, while the temperature of grass is 3℃ higher, and the temperature difference on cloudy days is reduced by about 65438 0℃.