Meteorology or Weather Terms +

(topics about the study of the complex motions and interactions of the atmosphere, including the observation of phenomena; such as, temperature, density, winds, clouds, and precipitation)

absolute humidity
1. The mass of water vapor in a given amount of the air.
2. The ratio of the mass of water vapor present in the air to the volume occupied by the gas.

The density of water vapor in the air is usually expressed as grams of water vapor per cubic meter of air.

adiabatic process
1. The process by which the temperature of the air changes without adding or taking away heat.
2. The changing of sensible air temperature without the gain or loss of heat to or from the surrounding air.
1. A reference to the processes of transport and mixing of properties (energy, heat, moisture, etc.) of a fluid by mass motion of that fluid in the horizontal plane.
2. In the atmosphere, the horizontal transfer of anything by the movement of air; for example, wind.

Common examples of advection include heat and moisture.

advection fog
Fog that forms when warmer humid air flows over cooler ground or water.
The study of the physics and chemistry of the upper atmospheres of planetary bodies, including he earth.

Atmospheric differences within the solar system often reflect the planet's or satellite's distance from the sun, the initial evolution of the planet, and the chemical reactions between the planet's air and its rocks.

The atmospheric equivalent to oceanic plankton, the term literally means "air wanderer" because aeroplankton, tiny plants, animals, and bacteria that live by eating, excreting, and even reproducing in the air are always at the mercy of the wandering wind.
1. A mixture of nitrogen, oxygen, argon, carbon dioxide, and other gases that make up the earth's atmosphere.

In ancient times, the name used for a gas.

2. The mixture of gases that make up the earth's atmosphere.

The principal gases that compose dry air are: Nitrogen, 78.09%; Oxygen, 20.95%; Argon, 0.93%; and Carbon Dioxide, 0.033%.

Another important constituent of air is water vapor which varies from 0% to about 4%.

air mass
A body of air in the lower atmosphere, which is more or less at a constant temperature and moisture content, and is often bounded by cold and warm fronts.
air pressure
Measured with a barometer, the force per unit area that the air exerts on any surface; it results from the collision of air molecules.
altocumulus clouds
Wool-pack clouds with patches or rolls of cloud joined together in a kind of sheet.
altostratus clouds
Pale, water clouds that form a translucent veil over the sun.
anabatic wind
A localized wind that is warmed by sunshine, rises, and blows up a slope.
1. A high-pressure area with closed circulation, which rotates clockwise in the Northern Hemisphere and counter clockwise in the Southern Hemisphere.
2. The center of high atmospheric pressure which spins in the opposite direction of a cyclone.
atmospheric pressure
The pressure created by the effect of gravity on the air above the earth.

The atmospheric pressure decreases as the higher altitude increases.

atmospheric science
A reference to the study of atmospheres on the planets and satellites of the solar system.

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