Assuming you're seeing the same thing I'm seeing: a lighter "halo" in the sky around the man on the left, and possibly also around some of the people near the river, I think it's not an intentional lighting effect but an accidental artifact.

My guess is that in the original exposure, the man was very, very underexposed. Post-processing techniques — possibly blending multiple exposures with HDR — were used to brighten it up. But this wasn't done carefully, and also caused brightening in the already-bright sky. This kind of halo is a very common artifact from this kind of brightness manipulation.