Oceanographic Conditions in Prince William Sound, CTD, Chlorophyll-a, and Zooplankton Data: 2010-2012, EVOS Herring Program

These data are part of the Herring Program of the Exxon Valdez Oil Spill Trustee Council, , project number 10100132-A, which is a multi-faceted study to determine why herring populations in Prince William Sound remain depressed since the early 1990s. Vessel surveys in Prince William Sound (PWS) were conducted several times per year during 2010 to 2012 to conduct Conductivity, Temperature, and Depth (CTD), water nutrient and cholorphyll-a, and zooplankton measurements. Surveys were timed around the “productivity season” to attempt to capture the spring and autumn blooms (i.e. pre-bloom, bloom and post-bloom). The surveys visited four PWS bays to maintain ongoing EVOSTC funded time series measurements. The historic datasets are from CTD surveys conducted by various agencies from the 1970s to 2009. This dataset includes three data types: 1) CTD casts. These data are presented as .zip files containing collections of CTD casts by year from 2010 - 2012. Each file contains the CTD data, gps track, event log, and archived paper logs. The CTD data is presented in various formats following routine processing using the SeaBird electronics SBE Data Processing software, and custom software written in MATLAB. Raw XML HEX data formats and converted ASCII CNV files are included in a file directory prefaced with a number indicating the processing step and text indicating what processing was done. Event logs contain station metadata for each cruise. 2) Chlorophyll-a concentration. These data are presented as a single comma-separated values (csv) file containing values of extracted chlorophyll-a concentrations at various depths and stations in Prince William Sound from 2010 to 2012. 3) Zooplankton concentration. These data are presented as a single csv file containing values of zooplankton concentrations, by species and stage, at stations in Prince William Sound from 2010 to 2012.