In sweden there is alot of variations of names like Nordahl. I'm not totaly shore, but I (who is a swede) have never heard that Grøndhal should be a swedish name. It's spelling looks more like it would be norweigen or danish. Rommedhal could be a swedish, but I have never heard it either. But it could come from the valley (dahl) around the swedish skiresort and village of Romme.
And for the name Skoglund, it probobly derives from the swedish words Skog and Lund. Skog means forest and Lund means grove. So It was given as a name to someone who lived in or nearby a forestgrove (Is it called that in english?).
Branting I don't know what it means. And It's hard to even gues.