Which process involves the transfer of heat from the body to the surrounding atmosphere?

Radiation is the process through which the body transfers heat to the surrounding atmosphere without requiring direct contact with a substance. This occurs through the emission of infrared rays from the body's surface, allowing the body to lose heat energy to cooler surroundings. It is a significant mechanism of heat loss, particularly in environments where the temperature is lower than the body temperature. This process is crucial for maintaining body temperature, especially during physical activity or when one is exposed to warmer environments.

While conduction involves direct contact between the body and another surface, and convection relies on the movement of air or liquid to carry away heat, radiation operates independently of such interactions, making it an essential method for thermoregulation in various conditions. Evaporation, on the other hand, involves the loss of heat through the conversion of liquid sweat to vapor, which also contributes to cooling but is different from the heat transfer mechanism of radiation.