Nice and subtle. Might I ask where you got the bird brushes? I made a few for myself, but my inability to draw a decent bird made them less than ideal. :)
This photo is interesting in that in many cases thick atmosphere like this creates a lighter haze around the base of objects while the colors darken and become more saturated towards the top of the objects. In this case, however, is seems that the light source coming from the right of the image is creating the opposite effect. I thought that was kind of cool. I feel like the right side of the image could be just a little warmer in color but that's about it. Nice job on this and capturing the effects of the light like you did. Looking forward to more posts!
Yes the buildings are lighter at the top which is a little unusual.The bird brushes can be found here: http://noctourniquet.deviantart.com/art/Corvidae-Ravens-N-Crows-31819490