Seward Line Conductivity, Temperature, and Depth (CTD) Data, 2012 to 2017, Gulf Watch Alaska Environmental Drivers Component

This dataset describes conductivity, temperature, and depth (CTD) data from stations along the Seward Line (a long-term observation transect on the Gulf of Alaska shelf) and Prince William Sound (PWS) in the Gulf of Alaska from 2012 to 2017. This dataset continues a long-term observation program which began in 1997 along the Seward Line and in PWS to assess the current state of the Northern Gulf of Alaska. During 2012-2016, 13 primary and 9 secondary stations along the Seward Line and 12 stations in Prince William Sound (eastern PWS stations were added in 2012) were sampled in May and early September from the USFWS vessel Tiglax. Each station includes high-resolution vertical profiling of water properties (including temperature, salinity, chlorophyll fluorescence, PAR, oxygen) to within 4 m of the bottom using a Seabird 911Plus CTD with dual temperature, conductivity and oxygen sensors. The CTD data have been archived in plain-text format as ASCII and HDR files output directly from the Seabird 911s using ASCII Out, with one file of each format provided for each study year (2012-2016).The HDR files contain the header information, which includes software version, sensor serial numbers, instrument configuration, station information, and cast notes of each cast file, and the ASCII files contain the readings of each profile. These data are part of the Gulf Watch Alaska (GWA), Pelagic Component of the Exxon Valdez Oil Spill Trustee Council, project numbers 12120114-J, 13120114-J, 14120114-J, 15120114-J, and 16120114-J. Gulf Watch Alaska is the long-term ecosystem monitoring program of the Exxon Valdez Oil Spill Trustee Council for the marine ecosystem affected by the 1989 oil spill.