Affiliation: | Department of Earth Sciences, University of Durham, Science Laboratories, South Road, Durham, DH1 3LE,;UK. E-mail: British Oceanographic Data Centre, Bidston Observatory, Bidston Hill, Prenton, Merseyside, CH43 7RA,;UK School of Ocean and Earth Science, Southampton Oceanography Centre, University of Southampton, European Way, Southampton, SO14 3ZH,;UK |