Not Unlike the Waves Lyrics

Lyric discussion by 2006200720082009 

Cover art for Not Unlike the Waves lyrics by Agalloch

Amazonis nailed what I was thinking. Here's an alternative interpretation: perhaps this is in relation to the fact that places like Norway (yes I know these guys are from Oregon) have periods in their winter where the sun does not rise at all due to their placement of the Earth. The scream of "Solstafir!!!" could actually be a yearning for the Sun to come back, though it does not despite this wish.