This is the visual definition icon responsible for specifying how a Thermodynamic diagram background is displayed. It controls features related to for instance isotherm, isobar and mixing ratio grids.
The macro language equivalent is mthermogrid().
The Thermo Plotting Editor
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isotherms, isobars, mixing ratio lines, dry and moist adiabats.
Info
From Macro/Python the icon can be called as mthermogrid().
