Humidity

Humidity is the amount of water vapor in the air. Water vapor is the gaseous state of water and is invisible. Humidity indicates the likelihood of precipitation, dew, or fog. Higher humidity reduces the effectiveness of sweating in cooling the body by reducing the rate of evaporation of moisture from the skin. This effect is calculated in a heat index table or humidex.

There are three main measurements of humidity: absolute, relative and specific. Absolute humidity is the water content of air at a given temperature expressed in gram per cubic metre.Relative humidity, expressed as a percent, measures the current absolute humidity relative to the maximum (highest point) for that temperature. Specific humidity is a ratio of the water vapor content of the mixture to the total air content on a mass basis.

Types

Absolute humidity

Absolute humidity is the total mass of water vapor present in a given volume of air. It does not take temperature into consideration. Absolute humidity in the atmosphere ranges from near zero to roughly 30 grams per cubic meter when the air is saturated at 30 °C.

Humidity (album)

Humidity (2000) is an album by the American ambient musician Robert Rich. It is a three disc set of live material recorded in 1998.

Disc one was recorded on April 2, 1998 at Stanford University’s KZSU radio station as part of their annual Day of Noise event. Disc two was recorded on May 9, 1998 at the Beyond Music Sound Festival in Venice, California. Disc three was recorded on May 10, 1998 during an in-store concert at the Moby Disc in Pasadena, California.

The composition for track two of disc one was originally released on the 1993 multi-artist compilation DeepNet. Track four of disc one and track five of disc three were co-composed with Brian “Lustmord” Williams and were originally released on Rich and Lustmord's 1995 collaboration Stalker. Track two of disc three was originally composed for Rich's 1994 collaboration with Lisa Moskow, Yearning. Track four of disc three is a reworking of Rich's 1994 release Night Sky Replies. All other material on this album was improvised.