# Estimating meteorological visibility from air chemical and particulate composition

I have found here an answer that provides formula that only takes into account vapors, pressure and temperature - What is the formula used for atmospheric visibility?

Is there an approach that also considers particulate matter and gases concentration? I am actually looking to account for as many contributing factors as possible, to achieve the best estimation, such as hydrometeors density,and whatever else may be related.

When you want to take into account as many contributing factors as possible, you will need a complete radiative transfer model, preferably a physics-based one (as opposed to fast radiative transfer models that are often incorporated into weather or climate models).

A radiative transfer model takes as input atmospheric composition in one or three dimensions, scattering databases for suspended matter such as aerosols or clouds (if the model includes scattering from particles), a molecular spectroscopic database such as HITRAN, as well as many configuration parameters. Some models are only valid for certain areas of the atmospheric spectrum. Some make line-by-line calculations (where "line" here means a location in the spectrum), others make broadband estimates directly. Examples of well-known line-by-line models that cover visible wavelengths include LBLRTM and LibRadtran. They may not be able to calculate visibility directly, but they should be able to calculate those quantities from which visibility can be estimated.

• Thanks, this is a great insight. Apr 23, 2022 at 11:18
• Such models, however, are not feasible for my use-case, and I am not versed enough in the sciences to deduce a simpler solution for visibility from such complex models. However now I understand that I phrased my question incorrectly. What I actually looking for is an analytical formula, that gives a sufficiently good estimate for horizontal visibility, and that takes into account multiple parameters from a single sampling point (or homogeneous atmosphere) Apr 23, 2022 at 11:24

This is best answered with the Koschmeider Equation. The Koschmeider Equation which estimates visible range based on the particulate matter is as follows:

Koschmeider Equation (units in ft. or m) = (1200 km μg/m^3 )/(particle concentration (μg/m^3 ) )

• A reference for this would improve the answer.
– Fred
Jul 6, 2022 at 8:30