My average body temperature is about 97.9F. Outside it is 97.9F. If my body temperature is the same as ambient temperature, why does 97.9F feel so damned hot to me?
Your body is generating more heat than it needs, and the outside temperature must be lower in order for the heat to be dissipated without extreme measures such as copious sweating.
Well, a partial answer (not getting into the perception of heat issue):
You are alive (presumably), and your metabolic activity produces heat that needs to be dumped somewhere - the ultimate sink for this is the surrounding air. When there is a nice temperature gradient, you feel comfortable. When the air is near, at, or above your body temperature, then it’s harder to get rid of your waste heat. Evaporative cooling is very effective at this, which is why we sweat on hot days or during exertion (excersize resulting in much more heat production than being sedantary). (Drink lots of water on hot days, and even more when excersizing.)
I guess an answer to the perception of heat issue may be that we are used to (adapted to?) living in a temperature much cooler than our core temperature; when it’s that hot out, then it just feels hot. Hope that helps.
One of the waste products of your body’s metabolic functions is heat. As the various chemical reactions are taking place within the cells of the body, heat is generated.
In order for the body to maintain temp, the body must “bleed” off excess heat. Kind of like a radiator on a car, with your skin being the human equivalent.
If the outside temp is the same as the target body temp, than there is no place for the heat to go.
Sweating does reduce skin temp by the energy exchange during the evaporation process. That is why dry climates don’t feel as hot as humid climates. The water on the skin evaporates more quickly and cools the skin more efficiently.
That’s why 90 degrees F in Albuquerque feels much cooler than 90 degrees F in New Orleans.