Open-source diagram illustrating lapse rates for introductory meteorology courses.
This diagram attempts to illustrate the connection between lapse rates and various atmospheric stability classifications. This diagram does have some limitations. These include:
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The numbers on the axes (but not in the legend) are arbitrary, since it's really only the slope of each profile that matters. Any of these profiles could be shifted left, right, up, or down, and still have the same stability classification as before.
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These profiles each illustrate a single lapse rate between the surface and 1 km altitude; in other words, they are all straight lines. Different layers of the atmosphere can simultaneously have different classifications (e.g., absolutely unstable at low levels and absolutely stable at upper levels) since in the real world, the profiles have wiggles and the lapse rate varies with height.
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The precise value of the moist adiabatic lapse rate actually varies quite a bit depending on temperature and pressure (anywhere from ~4 to just under 10°C/km), but we usually gloss over this at the intro level and use a single value, such as the 6°C/km value in this diagram. The dry adiabatic lapse rate value of 10°C/km is a good approximation throughout the troposphere and stratosphere.
All slopes are to scale. Lapse rates of 13°C/km to -4°C/km are shown, in increments of 1°C/km.
The diagram is provided in PDF, PNG, and editable PPTX formats.