Precipitation Chemistry In East Central Florida From 1978 To 1987

Rainfall was collected on the University of Central Florida campus and at the Kennedy Space Center over a 10 yr period between 1978 and 1987. The chemical composition has been determined and summarized by month, annual periods and for the entire ten year record at both locations. The weighted average pH at each site was 4.58; however, annual weighted average pH was above the 10 yr average during 4 of the last 5 years. Annual nitrate concentrations increased slightly during the latter half of the record while the annual excess sulfate concentrations remained below the 10 yr weighted average during 4 of the last 5 years. Stepwise regression suggests that sulfate, nitrate, ammonium ion and Ca played major roles in the description of rainwater acidity. Annual acid deposition and annual rainfall have varied from 20 to 50 meq H+ m-2 yr-1 and 100 to 180 cm yr-1, respectively. Sea salt comprises at least 25% of the total ionic composition. Trends in acidity, excess sulfate concentration and nitrate deposition have been observed in monthly data obtained at UCF.