☁️ Monte Carlo Photon Random Walk Through a Cloud Slab: Beer-Lambert, Albedo, Transmittance and the Two-Stream Check

Follow single photons through a cloud layer with the Monte Carlo method: random free flights from the Beer-Lambert law, absorption or Henyey-Greenstein scattering, and tallies of reflected, transmitted and absorbed light, checked against an independent delta-Eddington two-stream formula.