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Geosciences LibreTexts

10: Dynamics - Forces

  • Page ID
    3417
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    Learning Objectives

    By the end of this chapter, you should be able to:

    • explain mass conservation physically, recognize the mass conservation equation, and memorize its form when density is constant
    • state the three main conservation laws in atmospheric science: the conservation of mass, the conservation of momentum, and the conservation of energy
    • name and explain the three fundamental (real) forces in the atmosphere (gravity, pressure gradient, and friction)
    • name and explain the two new (apparent) forces that emerge when momentum conservation is written in the rotating reference frame
    • draw the balance of forces for geostrophic flow, gradient flow, geostrophic flow with friction, and cyclostrophic flow
    • explain why midlatitude winds are westerly

    Thumbnail: This low-pressure system over Iceland spins counterclockwise due to balance between the Coriolis force and the pressure gradient force. (Public Domain; NASA’s Aqua/MODIS satellite)


    10: Dynamics - Forces is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by William Brune (John A. Dutton: e-Education Institute) via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.