An instrument for measuring angles of inclination. Used in conjunction with a ceiling light to measure cloud height at night.

(1) The ratio of the speeds of a chemical reaction at two temperatures differing by 10

In a system of moist air, the dimensionless ratio of the mass of water vapor to the mass of dry air. For many purposes, the mixing ratio may be approximated by the specific humidity.

Generally, an instrument designed to measure or estimate the blueness of the sky. See Linke-scale.

A device for measuring sea-surface waves. It consists of a weighted pole below which a disk is suspended at a depth sufficiently deep for the wave motion associated with deepwater waves to be negligible. The pole will then remain nearly as if anchored to ...

The lowest value of a measured quality at which a sensor meets its accuracy specification.