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I know there are members here who have GRB Newman and other carbon canoes, and they may have experience with your question. I don't know GRB's layup schedule for fabric, resin and gel coat. However, on general principles, my understanding is that that carbon fabric itself is UV-resistant but that unprotected epoxy resin is not (if GRB uses epoxy). The epoxy would have to be protected by a UV-resistant gel coat or varnish. Again, it all depends on what GRB's layup is.
I'm not sure one month of UV exposure at a high latitude would do any significant damage to a carbon/epoxy layup with no gel coat, but I'd at least try to protect it with regular applications of 303 Protectant. Some folks protect their composite canoes with a custom made fabric canoe cover from a supplier such as
Redleaf Designs.