Definition

Thickness refers to the vertical distance between two pressure surfaces (isobars).

The thickness of a layer is related to the mean virtual temperature (Tv) according to the formula:

thickness equation

Where:

Note that for a given pair of pressures, the thickness is proportional to the mean virtual temperature (Tv) in the layer. The 1000:500 hPa thickness chart is perhaps the most common and is typically plotted with 60-meter contours. In this case, each contour reflects a mean virtual temperature change of 3°C.

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