The data represents the primary production measured by the C-14 assimilation method in the region of the California Current System (off Baja California), during spring, summer and fall of 1999. Additionally, primary production data of the region are shown of the tropical Mexican Pacific ocean of May 2001, March and August 2005 and November 2008.

C-14 assimilation method:The method consists of preparing a standard solution of sodium bicarbonate from the original reagent, using distilled water with a pH of 12. From this solution a known volume is added to mark (inoculate) the samples to determine the primary production. From the 100, 50, 30, 20, 10, 1 y 0.1% E 0(PAR) light depths, water sample were screened through a 150-μm net to exclude macrozooplankton. Three polycarbonate 250-mL bottles were filledwith this water and they were inoculated with 100 μL (5 μCi) of NaH14CO3. Two clear bottles were placed on transparent acrylic tubes along with a dark bottle per each depth. They were incubated at the original sampling depths for 2 hours, approximately at noon (local time). After incubation, samples were filtered through GN-6 membranes with 0.45 µm pore size and 25 mm diameter. All filters were placed on 20-mL borosilicate vials for scintillation liquid and 0.5 mL of 10% HCl was added in order to eliminate the inorganic 14C that was not fixed by phytoplankton during the photosynthesis. After 4 hours, 10 mL of Ecolite (scintillation liquid) were added to each vial. Radioactivity was determined with a Perkin Elmer scintillation counter. Primary production values (mg C m-3 h-1) were calculated from these radioactivity counts, according to Parsons et al. (1984), subtracting the carbon uptake of the dark bottles. The PP values were integrated through the euphotic zone using the trapezoidal integration method and expressed in mgC/m**2/h.

Supplement to: Sosa-Avalos, Ramón; Durazo, Reginaldo; Mitchell, Brian G; Cepeda-Morales, Jushiro; Gaxiola-Castro, Gilberto (2017): Phytoplankton photosynthetic parameters off Baja California: A tool to estimate primary production with remote sensing data. Ciencias Marinas, 43(3), 157-172