The Atmosphere
Home of the Weather

Any planet with a gaseous atmosphere will have weather of some form. Mars has dust storms which rage across its surface. Jupiter's Great Red Spot is believed to be a the top of a huge, deep storm. In the oppressively hot atmosphere of Venus, it rains sulphuric acid.

On Earth, the atmosphere is a very stable mixture of gases:

Atmosphere Components

Main Gases: Percent Content

Nitrogen 78%

Oxygen 20.9%

Argon 0.93%

Sub-total 99.8%

Variable consituents:

Carbon dioxide 200 to 400 parts per million

Water vapour 0% to 4%

Trace gases:

Ozone, Neon Helium

Krypton, Methane Sulphur oxides

Nitrogen oxides Hydrogen

Aerosols:

Dust Liquid water droplets

Salt particles Acidic droplets

The weight of the total atmosphere is 5.3 x 10¹⁸ kg = 5.3 x 10¹⁵ tonnes = 5.3 million, billion tonnes.

Its thickness relative to the diameter of the Earth is like the skin on an apple to the apple.

It is layered into several "spheres"

Thermosphere
Mesosphere
Stratosphere
Troposphere

However, it is only in the troposphere where weather as we know it is present. In the troposphere, the interaction between sunlight and the planet's surface causes unequal heating. The exchange of heat between the atmosphere and the ocean and land creates a heat engine which moves energy, air molecules and water.

Weather is the movement of air and water to exchange energy around the globe in an attempt to equalize temperature over the whole planet.

Learn More From These Relevant Books
Chosen by The Weather Doctor

Schaefer, Vincent J. and Day, John A.: A Field Guide to the Atmosphere, 1983, Houghton Mifflin Company, ISBN 0-395-33033-5.
Williams, Jack: The Weather Book, 1997, Vintage Books, ISBN 0-679-77665-6.

Written by
Keith C. Heidorn, PhD, THE WEATHER DOCTOR,
August 15, 2001