Thursday, 20 December 2007
Hot under the collar. Apparently.
This is a wet and dry bulb thermometer.
The dry bulb is the normal thermometer while the wet bulb has a fabric sleeve over it that is kept wet. When air passes over the wet sleeve, it cools due to evaporation and you can determine the humidity in the air by the difference in the two temperatures.
A wind chill factor, if you like.
In a totally humid area, like the tropics, little water would evaporate and the temperatures would be the same. In a dry climate there would be high evaporation and there would be a large difference between the two temperatures.
Which brings me to the local weather. There is a widget I have on my desktop that displays real and apparent temperature. Like so:
What I can't figure out is why should the apparent temperature be warmer than the actual temperature?
Any meteorologists out there?