Complex systems with weird behavior might describe both the global atmosphere and the Great Lakes. In this essay, noted environmental policy expert and author, Dave Dempsey says predicting climate change impacts on the Great Lakes is fraught with uncertainty.
Climate change is many things, but most of all it is surprise. So are the Great Lakes. Combine their complexity and you are likely to make fools out of anyone who makes flat predictions about how they will interact.
For example, the author of a book about the Great Lakes published in 2004 foresaw a future in which “water levels plummeted below the historic range beginning in 2016, responding to both climate change and growing water uses.” He has yet to admit his faulty prediction.
Until now. The author was me.
Having lived on the shore of a Great Lake from 2015 to 2017, I can accurately report that water levels are not below the historic range. In fact, on Lakes Michigan and Huron they are near the upper end of that range and could go higher. Week after week I observed waves gnawing at beaches and increasing storm damage.
That, however, does not mean climate change is not happening. It just means our ability to decode its future impacts is still developing – and perhaps is still in its infancy.
No one predicted the rise of toxic algae in western Lake Erie. Governments declared victory and pulled out the troops in the 1990s as algae blooms fell to tolerable levels after the disgraceful condition of the 1960s. By the early 2000s, the intolerable blooms were back and worsening. Warming waters are believed to be a contributing factor.
Great Lakes surprises reach way back before the days when climate change was a common term. Prior generations thought the lakes were vast enough to assimilate wastes. No one worried much about the sea lamprey until it unexpectedly migrated to the upper Great Lakes and literally devoured the native fishery.
But now we’re dealing with both surprising Great Lakes and surprising climate change.
In defense of those of us who envisioned parched Great Lakes as a result of climate change, that’s what the best models largely predicted 15 years ago. More recent predictions offered a moderated version of this view. In a 2015 report, the International Joint Commission (IJC) observed, “There is little agreement among studies of the impacts of future shifts in temperature and precipitation on [Great Lakes] water balances and lake levels … earlier studies suggesting large declines are giving way to newer studies suggesting smaller declines. If the current trend of progress in the science of climate change and translation of climate change into hydrologic responses continues, it is expected that uncertainty will decrease.”
Uncertainty will decrease. That is hardly a ringing declaration. It means that we must navigate in the dark, unsure where the shores or shoals are.
How do we do that?
One approach is also forthcoming from the IJC. In its draft first triennial assessment of progress under the 2012 Great Lakes Water Quality Agreement, released in January, the Commission proposed that the U.S. and Canadian governments “demonstrate global leadership” through a binational approach to Great Lakes climate change adaptation and resilience in the Great Lakes. Specifically, the Commission called for a vulnerability assessment to define climate change risks and technical support for measures to adapt to climate change. The Commission is expected to endorse the recommendation in its final version of the report, due this month.
While we don’t know exactly what climate change will bring to the Great Lakes, we know the range of potential impacts, from intense runoff after more severe storms, setting off a chain reaction of erosion, sedimentation, and nutrient loading, to the loss of cold and cool-water fish habitat, increased evaporation, decreased dissolved oxygen, shift in species range, algal bloom
In effect, the Commission is calling for a Great Lakes climate change agreement. Pooling scientific and technical resources, the U.S. and Canadian governments would analyze the most likely scenarios and help communities prepare for them with stormwater management systems, shoreline protection, and more– always keeping in mind the possibility that they’ll be wrong and need to adapt again.
This sensible recommendation has a meaningful underpinning: humility. In adopting it, governments would be admitting what they don’t know and preparing for surprises. That’s something public servants – and authors – will need to do more often as climate and Great Lakes conjure up the unexpected.
Dave Dempsey is Senior Adviser for FLOW – For Love of Water, a nonprofit organization based in Traverse City, Michigan.