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Great Lakes Sensitivity to Climatic Forcing
About the Project
NOAA Great Lakes Environmental Research Laboratory, in collaboration with a host of researchers from other academic and research institutions from the US and Canada, are working together to understand the Great Lakes' sensitivity to climate change, by looking at the paleontological record.
This project is a three-year, multidisciplinary, multi-institutional laboratory program funded by the National Science Foundation. It is designed to integrate knowledge bases of Great Lakes level oscillations and abrupt paleoclimate changes for input to paleohydrological response modeling. We will focus primarily on the millennium -scale environmental history of the central Great Lakes sector in the 9400-7700 cal yr BP (8.4-6.8 ka) time interval.
More information about the design and development of this project can be found in the Project Overview and Background sections of this website.
The GLERL portion of the project is led by Dr. Thomas E. Croley. GLERL will simulate Great Lakes hydrology under several candidate climate scenarios for alternative assumptions on lake and connecting channel conditions using a modified version of the Great Lakes Advanced Hydrologic Prediction System (AHPS).
The central question that GLERL will address is “what kind of changed climate would drive present Great Lakes hydrology to produce water levels that result in a ‘closed’ status where no outflow occurs, thereby becoming a terminal lake".
While this is not an attempt to simulate the past, this project will attempt to understand the possibility that changed climates of the past could have altered Great Lake levels sufficiently to produce closed-lake events after 9000 cal BP (Fig. 1)
More information about GLERL's role in the project can be found in the Hydrological Models section of this website.
Figure 1: Reconstruction of the paleogeography of the Huron, Erie and Ontario basins at 7600 14C BP showing posited shorelines of the closed lowstands (yellow) relative to potential open lake shorelinees (red) and present shorelines (white).
Why is this important?
Findings of this project will increase general awareness about the sensitivity of water levels to climate change and the utility of understanding impacts of paleoclimate change.
Evolution of the Great Lakes was previously thought to have resulted mainly from non-climatic processes such as opening/closing of outlets by ice retreat/advance, down cutting of outlets by erosion, and through differential glacial rebound. Corroboration of our hypothesis of a past high-amplitude climate change that drove lake levels below their outlet channels is a new aspect of the geological history of the Great Lakes, which can heighten societal interest in climate change.
The new knowledge stemming from this project about paleoclimate change impacts, when integrated with conventional methods of assessment of global warming, will contribute additional perspective and confidence for advice on policy or decision-making by government programs.
Adaptation to changes in lake levels is sensitive to the accuracy of future projections. It becomes important to understand the sensitivity of lake-level variation under conditions of future relatively higher-amplitude climate change.
Furthermore, this project could contribute evaluation of regional climate models, which could be further tested when the geological observations of former lake levels are compared with the hydrological outputs of paleoclimates and paleogeography of the Great Lakes as explored in this project.
Last updated: 2006-08-08 ks