High quality CTD data have been collected around New Zealand since the mid-1980s. This work examines the regional and temporal coverage of these data and compares them with existing regional and global climatologies. The adequacy of temporal resolution is investigated and seasonal cycles are calculated where possible.

Under development is a new T, S, and mixed-layer depth climatology incorporating all presently available data subject to appropriate quality controls. Preliminary results are presented, issues of representativeness examined, and critical areas for new data collection identified.