Does anyone know what this agalloch image means?

Sorry if this does not warrant its own thread, but can anyone tell me the meaning of this image and this rune: http://www.vivahaterecords.com/wp/wp-content/uploads/2010/10/agalloch_limitededition_small.jpg

It is on the cover of the limited edition of the marrow of the spirit album, and I was thinking of getting an agalloch tattoo and love this image, so want to know what it means.