Vertical sections of temperature, nitrate and chlorophyll fluorescence measured with instruments mounted on a SeaSciences Acrobat undulating, towed vehicle are shown in the three upper panels. The track of the tow through the upwelling center to the south of Aņo Nuevo Point is shown in the lower left. Distances in kilometers are marked at each corner. Monterey Bay is just to the south. The middle bottom plot shows nitrate concentrations plotted versus temperature, with each data point colored by the value of chlorophyll fluorescence. Note the linear relationship of nitrate and temperature, except in areas with very high fluorescence (equal to phytoplankton biomass). The lower right panel shows chlorophyll fluorescence plotted versus nitrate, with each point colored by temperature. Plots were made using Ocean Data View.