RV Clifford A. Barnes was a research vessel that was owned by the National Science Foundation and operated as part of the University-National Oceanographic Laboratory System fleet.

[1] Clifford A. Barnes began service as a United States Coast Guard icebreaking small harbor tug, USCGC Bitt.

[1][2] Built by Western Boat Building Co in 1965 for ice operations, search and rescue, and pollution response, she was one of fifteen of her class ordered by the Coast Guard.

[6] Although an October 2011 National Science Foundation inspection revealed that Barnes was still in generally good condition, its limited scientific and berthing capacity prompted the University of Washington to look for a replacement.

Although the replacement ship would still operate primarily in and around Puget Sound, Jensen Maritime Consultants were commissioned to draw up plans[7] for a vessel that will feature faster cruising speed, extended range, and increased berthing, among other improvements.