Chemical Sensor Program
In Situ Ultraviolet Spectrophotometer (ISUS)

ISUS nitrate data from M0 is plotted as small black points over a background of data points collected at Station M1 (1 to 5 m depth) during the previous 10 years. Each of the historical data points is colored by the Day of Year on which the sample was collected.  This coloring illustrates the systematic change in the NO3/ Temp. relationship over the course of the year.