Classical Newtonian physics can be used to describe atmospheric behavior. Namely, air motions obey Newton’s laws of dynamics. Heat satisfies the laws of thermodynamics. Air mass and moisture
are conserved. When applied to a fluid such as air, these physical processes describe fluid mechanics. Meteorology is the study of the fluid mechanics, physics, and chemistry of Earth’s atmosphere.
The atmosphere is a complex fluid system — a system that generates the chaotic motions we call weather. This complexity is caused by myriad interactions between many physical processes acting
at different locations. For example, temperature differences create pressure differences that drive winds. Winds move water vapor about. Water vapor condenses and releases heat, altering the temperature differences. Such feedbacks are nonlinear, and contribute to the complexity. But the result of this chaos and complexity is a fascinating array of weather phenomena — phenomena that are as inspiring in their beauty and power as they are a challenge to describe. Thunderstorms, cyclones, snow flakes, jet streams, rainbows. Such phenomena touch our lives by affecting how we dress, how we travel, what we can grow, where we live, and sometimes how we feel. In spite of the complexity, much is known about atmospheric behavior. This book presents some of what we know about the atmosphere, for use by scientists and engineers.