William Atkins
Wednesday, 11 February 2009 20:28
Science -
Health
Page 3 of 4
Absolute humidity is defined as the quantity of water in a particular volume of air.
One would measure AH by removing all the water in a volume
(V, air) of one cubic meter of air, and then weigh its mass
(m, water).
The amount of water vapor is the absolute humidity of that cubic meter of air. AH changes in value as the volume changes, even though the mass of water vapor has not changed. And, absolute humidity doesn't change with changes in temperature.
AH equals
m (water) divided by
V (air) and, thus, is expressed as grams per cubic meter, or other such units.
Shaman and Kohn analyzed previous data on flu virus survival and transmission with respect to absolute humidity.
Shaman said in the Science article “
Flu: It's the Humidity. Absolutely” that he doesn’t know why scientists didn’t test for absolute humidity in the past. Sharman surmissed,
“Maybe it's because they always see the local weatherman talking about relative humidity.”
The Oregon researchers found that absolute humidity affects influenza virus transmission (IVT) and influenza virus survival (IVS) much more than relative humidity.
Page four goes into more specifics on why Shaman and Kohn think absolute humidity is the key to fighting the flu.
