Unibrow Locos

I was wondering about the locomotives with the unibrow paint. Is it part of the newer horsehead scheme? I can't find a non-horsehead unibrow picture. When did this come into the paint scheme, and what is its significance?

The unibrow seems to have appeared when the first Horsehead -9 arrived which was the January 2003 built 9745.
www.rrpicturearchives.net/showPicture.aspx?id=672363
The unibrow is part of NS's latest paint scheme and an attempt to keep the heat soaking black paint off of the cab where the humans are. NS does not have Air Conditioning on all of its units so combining that with black paint and hot weather can make the cab rather toasty.
If you at this list this list there is at least one unit (9778) that has a unibrow, but by mistake has the old NS logo. Caused by swapping out engine compartment doors.
www.nsdash9.com/horsehead.html
www.rrpicturearchives.net/showPicture.aspx?id=914227

Thanks!

The unibrow started out as a full white windshield. I know a bunch of the flared SD70Ms and-9 wide bodies came with it, and a few are still around. As for crew comfort - I don't think that was the intention. That little itty-bit of white paint that isn't even on the top does nothing to help. Now NS did have at least one -9 standard cab that got a white roof ala CSX but that practice didn't continue.

And many of the white windshields became unibrows. A real shame - I kinda liked the full white faced engines.