Why is the wet-bulb temperature a good measure of how cool human ...

[colton]

Why is the wet-bulb temperature a good measure of how cool human skin can become?
  What will be an ideal response?

Question 2

Why are specific humidity and mixing ratio more commonly used in representing atmospheric moisture than absolute humidity? What is the only way to change the specific humidity or mixing ratio of an air parcel?
  What will be an ideal response?

[Bison]

Answer to Question 1

ANSWER: The wet-bulb temperature is the lowest temperature that can be reached by evaporating water into the air. On a hot day when the wet-bulb temperature is low, rapid evaporation (and, hence, cooling) takes place at the skin's surface. As the wet-bulb temperature approaches the air temperature, less cooling occurs, and the skin temperature may begin to rise. When the wet-bulb temperature exceeds the skin's temperature, no net evaporation occurs, and the body temperature can rise quite rapidly. Fortunately, most of the time, the wet-bulb temperature is considerably below the temperature of the skin.

Answer to Question 2

ANSWER: A rising or descending parcel of air will experience a change in its volume because of the changes in surrounding air pressure. Consequently, when a volume of air fluctuates, the absolute humidity changeseven though the air's vapor content has remained constant. For this reason, the absolute humidity is not commonly used in atmospheric studies. Specific humidity and mixing ratio, on the other hand, do not depend on the volume of the air. Specific humidity and mixing ratio can only change if water vapor is added or taken away from an air parcel.

[colton]

Thanks for the timely response, appreciate it

[xiazhe]

Gracias!