T S A C

TAHOE SCIENCE

ADVISORY COUNCIL

PROJECTS

Science to Action Plan (2019)

Three priority issues for Science to Action development are to:

1) quantify the impacts of future climate change on the aquatic environment – existing monitoring has established several climate driven trends, but the full extent of future changes will need to be adequately anticipated to inform planning decisions.

2) determine the causes of divergence in summer and winter clarity trends – while winter clarity improves, likely reflecting the success of past TMDL and EIP initiatives, summer clarity continues to decline.

3) assess current and future management decisions in response to both climate change and the evolving drivers of lake clarity.

The Tahoe Science Advisory Council (hereafter “Council”) proposes a set of recommendations to guide the investment of immediately available funding, with the overall objective of providing decision-relevant science that informs policy and that anticipates critical emerging issues relevant to lake water quality and ecosystem health. Implementation will require close coordination with resource agencies to develop the funding resources needed to sustain this objective over the long term.

Over the next two years, the Council will initiate four priority projects to address changing conditions in Lake Tahoe and provide recommendations for the data and tools needed to anticipate impacts and test management scenarios for building system resilience:

1) Conduct a broad assessment of available data to articulate and test the hypotheses for why summer and winter clarity are diverging.

2) Review and update existing tools for evaluation of clarity, lake and nearshore responses to changing climate and lake conditions. This includes the identification and filling of critical data gaps needed for enhanced model calibration and application that represent changes (e.g., meteorological data, hydrodynamic data, storm water data, food web interactions, etc.)

3) Evaluate fluxes of water and nutrients along transect(s) in the Lake Tahoe West watershed(s) and model their fate in nearshore and offshore regions of Lake Tahoe.

4) Initiate data synthesis and early assessment briefing workshops hosted by the Council to analyze ongoing data collection efforts and to develop statistical products relevant to modeling and for representation of status and trends of selected variables.

Project descriptions for these four priority near-term tasks have been included in downloadable document below along with a representation of the Council science vision that will inform longer-term application of science for action in the Tahoe Basin, as described below. The objective is to provide decision-relevant science that informs policy and that will anticipate critical or emerging issues relevant to lake water quality and ecosystem health.

Contact for further information: Alison Toy, natoy@ucdavis.edu