What is it with the Left and Science?

Here is another example of barbaric Left ideology - physics.

This from a blog on climate change;

Emission

Using Kirchhoff’s law, absorptivity of a material = emissivity of a material for the same wavelength and direction. For diffuse surfaces – and for gases – direction does not affect these material properties, so they are only a function of wavelength. (And for all intents and purposes, absorptance is the same term as absorptivity, and transmittance is the same term as transmissivity).

Emission of radiation at any given wavelength for a blackbody (a perfect emitter) is given by Planck’s law, which is usually annotated as B_λ(T), where T = temperature.

The absorptivity of a gas, a_λ = 1-t_λ =emissivity of a gas, ε_λ.
For a very small change in monochromatic radiation due to emission:
dI_λ = ε_λB_λ(T) .ds        [10a]
Therefore:
dI_λ = nσB_λ(T) .ds        [10b]
So if now combine emission and absorption, equations 1 & 10:
dI/ds = nσ.(B_λ(T) – I_λ)    [11]
If we combine this with our definition of optical thickness, from equation [4]:
dI_λ/dτ = I_λ – B_λ(T)     [12]
which is also known as Schwarzschild’s Equation – and is the fundamental description of changes in radiation as it passes through an absorbing (and non-scattering) atmosphere.
It says, in not so easy to understand English:

The change in monochromatic radiation with respect to optical density is equal to the difference between the intensity of the radiation and the Planck (blackbody) function at the atmospheric temperature

Sorry it’s not clearer in English.
In more vernacular and less precise terms:

As radiation travels through the atmosphere, the intensity increases if the Planck blackbody emission is greater than the incoming radiation and reduces if the Planck blackbody emission is less than the incoming radiation

When will this madness end?