Heat Radiation question (skin's reaction to UV versus IR radiation)

[haruspex]

Depends on what you mean by "peak"...

What is interesting to know is perhaps "most energy" i.e the area in the diagram in post #23

The difficulty applying that image to the question in this thread is that most of the visible light energy that doesn’t make it to earth’s surface (the yellow area in the visible band) is that which is reflected by clouds. The context of the question would be without clouds.
Of course, that also applies partly to the IR.

 

[malawi_glenn]

which is reflected by clouds

And rayleigh scattering...

The context of the question

Hard for me to know what the question(s) are at the moment.
We are pretty far from why cells react to IR radiation quicker than what they do to UV radiation...

 

[haruspex]

And rayleigh scattering...

Yes, there is Rayleigh scattering, but I would think most of it is what is blocked by clouds.

 

[malawi_glenn]

Yes, there is Rayleigh scattering, but I would think most of it is what is blocked by clouds.

Kinda depends on how you wanna phrase the question, like on an average square meter on the surface of the earth. Then you need to use the average cloud coverage which is IIRC around 60%?