I have recently wondered what exactly happens to the “atmosphere” when we shower. Does the air temperature increase with the warm mist coming from the water? Or, perhaps does the room temperature actually decrease due to evaporation? I think that the reason behind the room “feeling warmer” is due to humidity and not actual temperature change. And, of course, no matter what happens, we still feel cold when we get out due to water evaporating from the surface of our skin, thus heat being removed in the transfer. I wish I had a simple thermometer because I’m sure that many factors play in to the equation when we take into consideration the duration of the shower, pre-existing conditions, and water temperature, etc. In a nutshell though, what exactly happens to the air temperature?
Heat moves from hot bodies to cold. Assuming that your shower-water is warmer than the air in your bathroom, (and it almost certainly is, 72 F is chilly showering water) the air in your bathroom is getting warmer when you take a shower.
The humidity increase might increase the perceived temperature as well if the person entering the bathroom was actually sweating, but otherwise the simple humidity of the room won’t make that person feel warmer.
Basically, the water evaporating from the air (after the warming) is negligible?
I’m sorry, I’m not clear as to exactly what you’re refering to. Once the water is in the air as water vapor (humidity) there’s no where for it to evaporate to. It already is evaporated.
The water evaporating from your skin and other surfaces cools those surfaces it evaporates from and adds energy to the air, but doesn’t necessarily increase the air’s temperature. It does increase the enthalpy of the air which is a factor of the temperature and humidity of the air/water vapor mixture.
So when you shower, the temperature of the air is increased by convective heating from the warm water passing through it and the enthalpy of the air is increased by the rise in temperature and humidity. A higher enthalpy will feel warmer because the air is less effective at cooling you. If you somehow kept the moisture out of the air in your bathroom but allowed its temperature to increase while showering, it would feel MUCH cooler to you than normal when you stepped from the shower because of increased evaporative cooling.
To avoid the evaporative cooling chill when I step from the shower, I always dry off before I open the shower door.
I always do the same for the same reason.