vSmartMOM

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Quick Start ​

For: first-time users who want one successful forward radiative-transfer run.

Next: Configure a Scene (step by step), Compute Jacobians, RT basics.

This page is the 5-minute CPU path. It uses a tiny shipped scene so the first run does not require external line-data downloads or aerosol optics setup. The long-form tutorial remains available at Tutorial: Quick Start.

Run The Shipped Quickstart Scene ​

The quickstart scene is deliberately small: one spectral point, one Stokes component, two atmospheric layers, a Lambertian surface, and no absorption or aerosols. That keeps the first run focused on the core Rayleigh adding-doubling path.

julia
using vSmartMOM

scene = joinpath(pkgdir(vSmartMOM), "config", "quickstart.yaml")
params = read_parameters(scene)

model = model_from_parameters(params)
R, T = rt_run(model)

params is a mutable scene description. For example, this file already sets architecture: CPU(), but an interactive session can still override it before model construction:

julia
params.architecture = vSmartMOM.Architectures.CPU()

Inspect The Output ​

R is TOA upwelling radiance and T is BOA downwelling radiance. With unit incident irradiance they are radiances per unit irradiance, not dimensionless reflectance/transmittance. For unpolarized illumination, the TOA reflectance factor is π .* R[:, 1, :] ./ (cosd(params.sza) .* F₀_I), where F₀_I is the incident Stokes-I spectrum, broadcast over views.

R and T are three-dimensional arrays:

julia
size(R)
size(T)
R[:, 1, :]

The dimensions are:

  • view zenith angle

  • Stokes component

  • spectral point

For config/quickstart.yaml, both arrays have shape (1, 1, 1). Larger scenes increase these dimensions by adding more viewing angles, polarization components, or spectral samples.

Next Steps ​