NOAA Technical Memorandum (Tech Memos):

Every few years, a technical document (e.g., COPEPOD-2014, COPEPOD-2010, COPEPOD-2007, COPEPOD-2005) is created to summarize the full plankton database content and coverage and also presents the current/new methods or analyses applied to the database contents and data products.   For example, COPEPOD-2005 featured a significant improvement in methods and data coverage over the "World Ocean Atlas 2001 biomass fields (O'Brien et al. 2002)", while COPEPOD-2007 introduced an advanced data quality control method for plankton data.   COPEPOD-2014 reports on new content to the database, as well as presenting a minor update to both the COPEPOD-2005 biomass fields and the COPEPOD-2010 quality control methods.

If you are looking for Time Series methodologies and/or information, please see this page.