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5: Atmospheric Stability

  • Page ID
    46092
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    Alison Nugent and David DeCou

    Learning Objectives

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

    • Interpret stability based on the dry and moist adiabatic lapse rates
    • Understand how stability relates to vertical motion in the atmosphere
    • Describe and differentiate between the many lines on a Skew-T log-P diagram
    • Find the LCL, regions of CAPE and CIN, and the tropopause from a Skew-T log-P diagram

    • 5.1: Introduction
      This page explores atmospheric stability and instability, particularly in cloud formation, discussing how these conditions influence cloud shapes and are integral to thunderstorms. It uses analogies, such as a boulder, to clarify how air parcel movements relate to stability levels. Additionally, it emphasizes the significance of stability in weather events and the role of thermodynamic diagrams in understanding air parcel buoyancy.
    • 5.2: Atmospheric Stability and Lapse Rates
      This page explores atmospheric stability, emphasizing the roles of environmental lapse rates and moisture. It describes absolute instability, where higher environmental lapse rates enable warm, less dense air parcels to rise, and conditional instability, where buoyancy relies on saturation. Unsaturated parcels resist rising, while saturated ones can ascend.
    • 5.3: Skew-T Log-P Diagram
      This page covers Skew-T Log-P diagrams, key for analyzing atmospheric data via temperature and pressure representation. It details essential components such as isobars and lapse rates, and illustrates interpretation with a radiosonde example from Lihue, Hawaii. The page explains finding the lifting condensation level (LCL), which indicates cloud base, and describes the cooling process at moist adiabatic rates.
    • 5.4: CAPE and CIN
      This page covers two fundamental thermodynamic concepts in atmospheric science: Convective Available Potential Energy (CAPE) and Convective Inhibition (CIN). CAPE measures buoyant energy for thunderstorms, while CIN represents the energy that restrains convection. Additionally, it teaches how to identify the tropopause in temperature soundings and introduces the Skew-T Log-P diagram for analyzing these thermodynamic parameters.


    5: Atmospheric Stability is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.