The mass of water vapor in a parcel divided by the mass of the dry air in the parcel (not including water vapor)
Ratio of the concentration of one atmospheric constituent to the others, sometimes given in parts per million per volume (ppmv) or parts per billion per volume ( ppbv).
humidity measure, defined as the dimensionless ratio of the mass of water vapor to the mass of dry air. The mixing ratio is usually expressed in units of grams of water vapor to kilogram of dry air.
the ratio of the mass of water vapor in a system to the mass of dry air
An absolute measure of the amount of water vapor present in a given amount of dry air. The quantity is measured in grams of water vapor per kilogram of dry air. It is analogous to the relative humidity in that it measures the amount of moisture present in the atmosphere, but it is a more open ended quantity. Very dry (desert-like) air will have values in the 1g/kg range or lower, while very moist tropical air can exceed 20 g/kg at the ground.
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.
A measurement of the amount of water vapor in the air of a given sized quantity of dry air; grams of vapor per kilogram of dry air.
The ratio between the weight ( mass) of water vapor (or some other gas) held in the atmosphere compared to the weight of the dry air in a given volume of air. Usually measured in grams water vapor (or gas) per kilogram of dry air.