Figure 4

Time series for 1999 compared to historic (1989 - 1997) monthly average values (boxes depict median, 10, 25, 75 and 90 percentiles):
a) daily total ammonia loads from Metro
b) total ammonia concentrations for the upper waters (mean of 0, 2, and 4 m values) of Onondaga Lake; dashed line is New York State standard for 1999 conditions
c) phytoplankton biomass and composition (1 m).