TheHutt said:

Even if it's there, there is no evidence that it actually shouldn't be there. ;)

Well yeah, I certainly agree that it seems that the filmmakers intended it to be there, considering that The Desolation of Smaug shares pretty much the same blanket green tint as An Unexpected Journey.

Its just my personal preference that clouds look more white instead of green and since others seem to share my preference as well, I share the regraded releases I've done that fix this. Whether it officially should or shouldn't be there honestly doesn't concern me either way, only what looks more appealing to my eyes when watching the films, which is without the blanket green tints.