36℃≠36℃? The perceived temperature is off the charts! How to stay cool in the heat and humidity?

As the impact of global climate change becomes increasingly significant, high temperature and high humidity weather frequently occurs around the world. This kind of weather not only makes us feel uncomfortable, but also may pose a serious threat to health. Now, let's analyze the hazards of high temperature and high humidity weather and provide scientific and practical protective measures to help you safely spend the hot and humid summer together.

1. Hazards of high temperature and high humidity

High temperatures alone can cause a lot of discomfort to the human body, but when high temperatures are combined with high humidity, the situation becomes even more severe. This is because:

- High humidity will reduce the efficiency of sweat evaporation and affect the body's heat dissipation

- The perceived temperature is often higher than the actual temperature, increasing the risk of heat stroke

- Prolonged exposure to high temperature and high humidity may cause heat fatigue, heat cramps, and even heat stroke

2. Perceived temperature: the "combined effect" of temperature and humidity

The perceived temperature is a comprehensive indicator that combines air temperature and relative humidity, which reflects the actual temperature felt by the human body. This is why we still feel hot and unbearable at a temperature of 28 degrees.

The calculation formula for body temperature takes into account the effects of air temperature, relative humidity and wind speed on body temperature. The following is a simplified calculation formula for body temperature:

Perceived temperature AT = actual temperature T + 0.348 × relative humidity RH − 0.7 × wind speed WS + 0.7

in

( AT ) is the perceived temperature (Celsius)

( T ) is the actual temperature (degrees Celsius)

(RH) is the relative humidity (percent)

( WS ) is the wind speed (m/s)

The body temperature is suitable for temperature perception under normal circumstances

For example: When the temperature is 28°C, the relative humidity is 90%, and the wind speed is 5 m/s:

Feeling temperature (Celsius) ≈ 28 (Celsius) + 0.348 × 90 (percentage%) - 0.7 × 5 (meters/second) + 0.7 ≈ 56.52°C

This means that even if the temperature shown on the thermometer is 28°C, the actual temperature felt by the human body may be as high as 56.52°C! This is the power of hot and humid weather!

3. Scientific protective measures

In the face of high temperature and high humidity, we can take the following measures to protect ourselves:

3.1 Indoor environment adjustment

- Use air conditioning: according to personal feeling, set the temperature to around 26℃ and the relative humidity to 40-60%

- Ventilation and cooling: Open windows for ventilation in the morning and evening, and draw curtains during the day to block direct sunlight

- Use a dehumidifier or dehumidification mode: In humid areas, a dehumidifier can effectively reduce indoor humidity. When it is hot and humid, the dehumidification mode of the air conditioner is also a good choice.

3.2 Personal protection

- Clothing: Choose light, light-colored, loose clothing to help dissipate heat

- Hydration: Drink warm water regularly and avoid drinking too cold drinks

- Sun protection: Wear sunscreen, a hat and sunglasses when going out

- Adjust your work and rest schedule: avoid going out during the hot noon hours and take a proper lunch break

- Location of a cool place: If you feel the heat and humidity are unbearable, find a cool place nearby in time

3.3 Dietary adjustment

- Eat more fresh fruits and vegetables to replenish vitamins and water

- Increase salt intake appropriately to replenish electrolytes lost through sweating

- Eat less high-fat and high-protein foods to reduce the burden on digestion

3.4 Exercise precautions

- Choose cooler times of the day such as early morning or evening to exercise

- Increase the intensity of exercise gradually and pay attention to hydration

- If you feel unwell, stop exercising immediately and find a cool place to rest

4. Precautions for special groups

- Elderly people: Pay special attention to indoor temperature regulation and avoid strenuous exercise

- Children: Stay hydrated and avoid playing outdoors for long periods of time

- Patients with chronic diseases: take medication as directed by the doctor and pay close attention to your physical condition

5. Emergency situations need to be handled

If you experience symptoms such as dizziness, nausea, or burning skin, these may be signs of heat stroke. You should immediately:

1. Move to a cool and ventilated place

2. Undress and wipe your body with cold water

3. Replenish water and electrolytes

4. If the condition is serious, seek medical attention immediately

at last

High temperature and high humidity are indeed very uncomfortable. We need to take some protective measures to safely get through the hot and humid weather. We should pay attention to weather changes in a timely manner, take scientific protective measures, and get help in time when problems arise!

References

1. Steadman, RG (1979). The assessment of sultriness. Part I: A temperature-humidity index based on human physiology and clothing science. Journal of Applied Meteorology, 18(7), 861-873.

2. Kjellstrom, T., Briggs, D., Freyberg, C., et al. (2016). Heat, human performance, and occupational health: A key issue for the assessment of global climate change impacts. Annual Review of Public Health, 37, 97-112.

3. Guo, Y., Gasparrini, A., Armstrong, BG, et al. (2017). Heat wave and mortality: A multicountry, multicommunity study. Environmental Health Perspectives, 125(8), 087006.

4. World Health Organization. (2021). Heat and health fact sheet.

5. China Meteorological Administration. (2023). Guidelines for the prevention of heat stroke. Meteorological Press.