Measurement and interpretation of acid rainfall in the Los Angeles basin

Book · Tue Jan 01 04:00:00 EST 1980

OSTI ID:5529172

Morgan, J J; Liljestrand, H M

The purpose was to define the extent, degree and pertinent chemical characteristics of acid precipitation in the Los Angeles basin of southern California. Precipitation samplers were placed at nine locations: Pasadena, Westwood and Wrightwood. Increments of precipitation collected during a storm were analyzed for pH, titration acidity, chloride, nitrate, nitrite, sulfate, potassium, calcium, magnesium, ammonium, organic carbon and suspended solids. The mean acidity in the fall-spring 1978-79 period ranged from a high of 38.4 microequivalents/liter at Pasadena to a low of 2.45 microequivalents/liter at Big Bear Lake, with corresponding mean pH's of 4.41 at Pasadena and 5.42 at Big Bear Lake. Incremental sampling during storms revealed significant changes in pH and chemical composition with time, with early stages of precipitation generally showing low pH and high nitrate and sulfate concentrations. For the fall-spring 1978-79 period the mean ratio of nitrate to nonsea salt sulfate in precipitation varied from 0.4 at Long Beach to 2.8 at Big Bear Lake. The mean ratio at Pasadena was 0.9. Data on chemical composition of precipitation indicate that the observed net acidity is the result of partial neutralization of the strong acids H/sub 2/SO/sub 4/ and HNO/sub 3/ by basic NH/sub 3/ and metal carbonates and oxides from soil dust. Nitrate and nitrite in rainfall at Pasadena are correlated significantly with rainfall intensity, atmospheric ozone concentration and atmospheric nitric oxide concentrations. The same correlation is found for sulfate in rainfall. Inverse correlation of nitrates and sulfate with rainfall dilution effect. For both nitrate and sulfate in rainfall correlation is observed with Pb aerosol and total aerosol particulate matter.

• OSTI ID: 5529172
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ACID RAIN
AIR QUALITY
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
ATMOSPHERIC PRECIPITATIONS
CALCIUM COMPOUNDS
CALIFORNIA
CARBON COMPOUNDS
CHALCOGENIDES
CHEMICAL COMPOSITION
CHLORIDES
CHLORINE COMPOUNDS
ECOLOGICAL CONCENTRATION
ELEMENTS
ENVIRONMENTAL QUALITY
FEDERAL REGION IX
HALIDES
HALOGEN COMPOUNDS
LEAD
MAGNESIUM COMPOUNDS
METALS
NITRATES
NITRIC OXIDE
NITRITES
NITROGEN COMPOUNDS
NITROGEN OXIDES
NORTH AMERICA
OXIDES
OXYGEN COMPOUNDS
OZONE
PH VALUE
POTASSIUM COMPOUNDS
RAIN
SULFATES
SULFUR COMPOUNDS
USA