Analyzing Legacy Data in a Climate Context to Decipher Modern Changes in Lake Water Chemistry

storm cloudInstitution: University of Maine
Sponsor: Maine Water Institute (WRRI)

This project combines existing data, newly developed landscape data, down scaled climate models, and multivariate and time-series statistical techniques to quantify the effects of extreme events on acid-relevant surface water chemistry. The project documents the nature, timing, and frequency of extreme climatic events for over 400 lakes across New England and New York by coordinating data analysis of lake and stream water data from US EPA long-term research and monitoring projects. This analysis consists of biogeochemical measurements taken over the past three decades by multiple agencies including the USGS, National Park Service, Adirondack Lakes Survey Corporation, and cooperating universities across the Northeast.

Data from this project have been used to evaluate trends in surface water acidification and evidence for recovery in acid-sensitive regions in the northeastern US in response to the Clean Air Act Amendments. This project integrates extreme weather data and watershed and hydrogeomorphic characteristics for each lake into a legacy database that includes over 3,000 biogeochemical measurements. Multivariate statistical analyses and routines optimized for time series, landscape analysis, and trend detection will be used to characterize the biogeochemical response of different lake types to extreme weather events.

The results provide a framework for evaluating this response for resource managers, and a set of extreme event responses for different lake types that can be used to model the effects of future changes in extreme events. Further, the responses in different lake types can be used to refine expectations of ‘recovery’ from acidification, and re-define site selection and statistical techniques currently used in assessment of trends in response to atmospheric sulfur reduction.

Finally, understanding the links among extreme climate events, reduced sulfur deposition, and watershed characteristics will aid drinking water utilities in assessing the degree of risk and required treatment strength with dissolved organic carbon fluctuations in their water source during extreme weather years.

Team Members

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