Comparison of MAGIC and Diatom paleolimnological model hindcasts of lakewater acidification in the Adirondack region of New York

Technical Report · Thu Feb 28 23:00:00 EST 1991

DOI:https://doi.org/10.2172/5927671· OSTI ID:5927671

Sullivan, T J; Bernert, J A; Eliers, J M ^[1]; Jenne, E A ^[2]; Cosby, B J ^[3]; Charles, D F; Selle, A R ^[4]

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1. E and S Environmental Chemistry, Corvallis, OR (USA)
2. Pacific Northwest Lab., Richland, WA (USA)
3. Duke Univ., Durham, NC (USA). School of Forestry and Environmental Studies
4. Environmental Protection Agency, Corvallis, OR (USA). Environmental Research Lab.

Thirty-three lakes that had been statistically selected as part of the US Environmental Protection Agency's Eastern Lake Survey and Direct Delayed Response Project (DDRP) were used to compare the MAGIC (watershed) and Diatom (paleolimnological) models. The study lakes represented a well-defined group of Adirondack lakes, each larger than 4 ha in area and having acid-neutralizing capacity (ANC) <400 {mu}eq L{sup {minus}1}. The study first compared current and pre-industrial (before 1850) pH and ANC estimates from Diatom and MAGIC as they were calibrated in the preceding Paleocological Investigation of Recent Lake Acidification (PIRLA) and DDRP studies, respectively. Initially, the comparison of hindcasts of pre-industrial chemistry was confounded by seasonal and methodological differences in lake chemistry data used in calibration of the model. Although certain differences proved to be of little significance for comparison, MAGIC did predict significantly higher pre-industrial ANC and pH values than did Diatom, using calibrations in the preceding studies. Both models suggest acidification of low ANC Adirondack region lakes since preindustrial times, but differ primarily in that MAGIC inferred greater acidification and that acidification has occurred in all lakes in the comparison, whereas Diatom inferred that acidification has been restricted to low ANC lakes (<about 50 {mu}eq L{sup {minus}1}). 133 refs., 30 figs., 16 tabs.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA)
• Sponsoring Organization: EPA; Environmental Protection Agency, Washington, DC (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 5927671
• Report Number(s): PNL-7487; ON: DE91010125
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540320* -- Environment
Aquatic-- Chemicals Monitoring &amp; Transport-- (1990-)
ACID NEUTRALIZING CAPACITY
ACID RAIN
ACIDIFICATION
ADIRONDACK MOUNTAINS
ANIONS
APPALACHIAN MOUNTAINS
AQUATIC ECOSYSTEMS
ATMOSPHERIC PRECIPITATIONS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CATIONS
CHALCOGENIDES
CHARGED PARTICLES
CHEMISTRY
ECOSYSTEMS
FEDERAL REGION II
HISTORICAL ASPECTS
ION EXCHANGE
IONS
LAKES
MATHEMATICAL MODELS
MOUNTAINS
NAPAP
NEW YORK
NORTH AMERICA
OXIDES
OXYGEN COMPOUNDS
PH VALUE
RAIN
SEASONAL VARIATIONS
SOILS
STATISTICAL MODELS
SULFATES
SULFUR COMPOUNDS
SURFACE WATERS
USA
VARIATIONS
WATER CHEMISTRY
WATERSHEDS