Under what circumstance does the risk of hypothermia significantly increase?

The risk of hypothermia significantly increases when an individual is immersed in cold water. This is because the body loses heat much faster in water than in air. Water conducts heat away from the body approximately 25 times more effectively than air at the same temperature. When a person is exposed to cold water, especially if the water temperature is below 70°F (21°C), the body can rapidly lose heat, leading to a drop in core body temperature and potentially resulting in hypothermia.

In addition, immersion in cold water can cause the body to react in ways that can accelerate heat loss, such as vasoconstriction, which reduces blood flow to the extremities and can lead to loss of dexterity and coordination. This condition is particularly dangerous for individuals who may be unable to get out of the cold water quickly, as the longer they stay submerged, the greater the risk of developing hypothermia becomes.

Other situations, such as being in hot weather conditions or swimming in warm water, do not present the same risk for hypothermia because the body is exposed to temperatures that are conducive to maintaining heat rather than losing it. Wearing a wetsuit can provide thermal insulation and slow the rate of heat loss in cold water, thus reducing