Response of lake chemistry to changes in atmospheric deposition and climate in three high-elevation wilderness areas of Colorado

Mast, MA; Turk, JT; Clow, DW; Campbell, DH

HERO ID

1711004

Reference Type

Journal Article

Year

2011

HERO ID 1711004
In Press No
Year 2011
Title Response of lake chemistry to changes in atmospheric deposition and climate in three high-elevation wilderness areas of Colorado
Authors Mast, MA; Turk, JT; Clow, DW; Campbell, DH
Journal Biogeochemistry
Volume 103
Issue 1-3
Page Numbers 27-43
Abstract Trends in precipitation chemistry and hydrologic and climatic data were examined as drivers of long-term changes in the chemical composition of high-elevation lakes in three wilderness areas in Colorado during 1985-2008. Sulfate concentrations in precipitation decreased at a rate of -0.15 to -0.55 mu eq/l/year at 10 high-elevation National Atmospheric Deposition Program stations in the state during 1987-2008 reflecting regional reductions in SO2 emissions. In lakes where sulfate is primarily derived from atmospheric inputs, sulfate concentrations also decreased although the rates generally were less, ranging from -0.12 to -0.27 mu eq/l/year. The similarity in timing and sulfur isotopic data support the hypothesis that decreases in atmospheric deposition are driving the response of high-elevation lakes in some areas of the state. By contrast, in lakes where sulfate is derived primarily from watershed weathering sources, sulfate concentrations showed sharp increases during 1985-2008. Analysis of long-term climate records indicates that annual air temperatures have increased between 0.45 and 0.93A degrees C per decade throughout most mountainous areas of Colorado, suggesting climate as a factor. Isotopic data reveal that sulfate in these lakes is largely derived from pyrite, which may indicate climate warming is preferentially affecting the rate of pyrite weathering.
Doi 10.1007/s10533-010-9443-4
Wosid WOS:000287750100003
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000287750100003
Is Public Yes
Keyword Atmospheric deposition; Water chemistry; Lake; Climate; Trends; Weathering; Alpine