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Skew-T Log-P

Title text: The most important quantity for meteorologists is of course the product of latent pressure and temperostrophic enthalpy, though 'how nice the weather is' is a close second.

Explanation

This explanation may be incomplete or incorrect: Created by CHATGPT FOR SOME REASON - This needs an explanation. Do NOT delete this tag too soon.

The comic is a funny take on a skew-T log-P diagram (the name comes from the temperature (T) lines being skewed at a 45-degree angle, and the pressure (P) lines being logarithmic in scale). These diagrams are mostly used to plot atmospheric soundings, which are usually made by sending a weather balloon up into the air.

Because the diagrams have a lot of lines on them (isobars, isotherms, adiabats, and mixing ratios, and that's before plotting the actual measurements of temperature and dewpoint temperature), they can be hard to understand if you haven't learned how to. The comic pretends to offer an explanation of how to interpret one such diagram (which may appear to have measurements from two separate weather balloons, one with two solid black lines for its measurements and the other with two dashed black lines, whereas the two lines and various styles of line generally mean different measurements from the same balloon-track), but most of the explanations are blatantly incorrect or humorous in nature.

Item in comic	Correct?	Explanation
Pressure latitude
Enthalpic pressure
Entropic density
Latent heat of cooling
Isobars		lines on a map denoting where equal air pressures exist when the map was composed.
Omnitrophic wind
Isomers	No	different forms of molecules with the same formula, with the atoms or functional groups arranged differently. An example would be propanol, which has three. One of the most common isomers of propanol has its OH functional group in the middle, so is called isopropyl alcohol or isopropanol. However, these are actually isotherm lines, representing equal temperature.
Line of constant thermodynamics
Uncomfortably moist adiabat
Oops, the balloon flew through a ghost
These lines are slightly different because Dave messed them up
No birds up here :(	Yes*	This point is near the top of the diagram, with an air pressure of about 110 millibar (about 15 kilometers above sea level). This is well above the highest flight height of any known bird species. However, this information is irrelevant to the purpose of a skew-T log-P diagram.
Track of rising weather balloon
Track of popped balloon falling back down
Meteogenesis
Seems bad
Dew point	Real but misrepresented.	The temperature at which water condenses out of the air, and therefore dew starts to form, given the level of water vapor in the air. It is shown here as an actual singular point, when it should be a line (typically the leftmost solid plotted line) representive of which temperature 'dew' should form at any given pressure.
Heavyside layer		Probably a misspelling of "Heaviside," the surname of the co-discoverer of what we now call the E region of the ionosphere. Co-discovered by Arthur E. Kennelly and Oliver Heaviside.
These lines are tilted because the wind is blowing them
Don't stand here or you might get hit by a balloon

An actual Skew-T Log-P diagram, with several real annotations.

The true design of a Skew-T Log-P diagram is intended to best represent the nature of the weather in any given column of atmosphere. The pressure (vertical axis, with pressure being closely but not directly synonymous to altitude) is shown as a logarithmic scale (i.e. Log-P) due to the more practical separation of values. As height increases, relevent changes in the atmosphere also generally become more spaced out. A linear scale would create a 'busy' area at a lower plot and an effectively featureless upper stretch. The temperature scale is deliberately tilted, rather than orthagonal, which (together with the logarithmic nature of the pressure scale) allows the typical way that temperatures fall with altitude(≈pressure) to trend roughly vertically, give or take the notable changes that are key to understanding the forecast. Other measurement lines, differently skewed and often also curving across the temperature/pressure skewed-log 'grid', represent various other idealistic relationships (where both T and P vary, keeping another measure constant) that are useful references to meteorologists.

Upon this style of graph are plotted the actual measurements obtained by (e.g.) releasing a weather balloon. As well as the variation of actual temperatures and pressures, other retrieved data is plotted, such the dew point. The dew point is a function of how the humidity of the air interacts with any given temperature and pressure to produce condensation. By observing how the actual measurements and dew point line converge and cross, the development and nature of clouds can be tracked and pinned to specific cloud layers. Further details may also be included, such as wind-direction and wind-speed indications (often to the side of the plot) to give a visual cue about possible wind shear and/or to suggest which direction of adjacent weather-station readings may hold clues as to what changes may later blow in above the current site.

Transcript

This transcript is incomplete. Please help editing it! Thanks.

How to Interpret a Skew-T Log-P Diagram

[The comic shows a skew-T log-P diagram. On it are various labels, including isobars, comments, and other interpretations of the diagram.]

[Left to the diagram is an upwards-pointing arrow with the label "Pressure Latitude". Right to the diagram is a downwards-pointing arrow with the label "Entropic Density". Below the diagram is a right-pointing arrow with the label "Enthalpic Pressure".]

[The remaining labels are inside the diagram.]

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