A 265-Year Reconstruction of Lake Erie Water Level
Wiles, G.C., Krawiec, A.C. and D'Arrigo, R.D. 2009. A 265-year reconstruction of Lake Erie water levels based on North Pacific tree rings. Geophysical Research Letters 36: 10.1029/2009GL037164.
In the present study Wiles et al. (2009) compared eighteen temperature sensitive ring-width series of trees from the Gulf of Alaska region with monthly Lake Erie water levels over a common period of 87 years, deriving a good relationship between the ring-width series and mean annual lake levels, after which the four ring-width series found to be most highly correlated with the Lake Erie water levels were used to extend the total length of the lake level history to 265 years."
The results of the researchers' analysis are presented in the figure below, where it can be seen, as they state, that "reconstructed extremes have approached but not exceeded the late 20th century high levels [italics added]." And in the concluding sentence of the abstract of their paper, they reiterate that "the highest lake levels in the reconstruction are found over the past few decades."
Annual mean water level of Lake Erie vs. time, as directly measured (green line) and reconstructed (blue line). Adapted from Wiles et al. (2009).
So how has it happened? In discussing their findings, Wiles et al. remark that "the recent higher stands in the 1970s-1990s, and perhaps the steady rise in lake levels over the past 100 years, may be linked to a rise in Gulf of Mexico-derived precipitation that has generally outpaced increased evaporation," and they report that "similar increases in precipitation and humidity have been noted for Lake Michigan (Sellinger et al., 2008) and relative humidity in the general lower Great Lakes regions (LaValle et al., 2000)." Once again, therefore, we have another example of model-based climatic concerns ultimately being replaced with real-world good news.
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LaValle, P.D., Lakhan, V.C. and Trenhaile, A.S. 2000. Short term fluctuations of Lake Erie water levels and the El Niņo/Southern Oscillation. Great Lakes Geography 7: 1-8.
Sellinger, C.E., Stow, C.A., Lamon, E.C. and Qian, S.S. 2008. Recent water level declines in the Lake Michigan-Huron system. Environmental Science and Technology 42: 365-373.