Prince William Sound Chlorophyll-A and Nutrient Data, 2012 to 2016, Gulf Watch Alaska Environmental Drivers Component

These data are part of the Gulf Watch Alaska (GWA), Environmental Drivers 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. This dataset contains chlorophyll-A and nutrient data analyzed from water samples collected by Nisken bottles attached to a rosette during conductivity, temperature, and depth (CTD) up-casts at 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 2016. 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. Data were collected from 13 primary and 9 secondary sampling stations along the Seward Line and 12 stations in Prince William Sound (eastern PWS stations were added in 2012) sampled in May and early September from the USFWS vessel Tiglax. Chlorophyll-a concentrations were determined at all stations as a measure of phytoplankton biomass and as a means to calibrate in vivo fluorescence sensors on the CTDs. Additionally, concentrations of phosphate, silicate, nitrate, nitrite, ammonium, and phaeopigments were measured from Niskin bottle samples. These files have been archived in CSV format, with two files for each survey year: spring and fall survey cruises. File names reflect ship name, surveys and year (e.g., TXS12_nut_chl_final.csv for the spring survey 2012, TXF13_nut_chl_final.csv for the fall survey of 2013 where TX-Tiglax S-Spring and F-Fall). Spring cruises were conducted during May and Fall cruises were conducted during September.