The north is getting hotter, and Lake Superior may be witnessing accelerating effects of global warming. Boreal forests are burning, and those fires may increase mercury levels in aquatic ecosystems. Precipitation patterns are changing. Lake ice is decreasing; evaporation in increasing. These changes affect the health of forests, fisheries, wildlife, and people who live in the watershed.
As I write this on a December night, in a little cabin on the south shore of Lake Superior, wind chill warnings are going out over the weather networks. 40 below wind chills are predicted. Exposed skin can freeze in ten minutes, the weather radio insists. "If you have to venture outside," we’re told, "cover all extremities. Carry emergency gear. Stay home if possible."It’s hard to believe in global warming on a night like this. The wind whips off Lake Superior, thrusting snow eddies into the cabin every time I crack the door for more wood. Could a few extra degrees in annual temperature averages make much difference, locals ask. In Cornucopia's general store, people stand around the pellet stove stomping feeling back into their toes and joking about how maybe we could use a little of that global warming right about now. Thaw out those frozen septic systems. Cut down on those heating bills.
But underneath the jokes, everyone up here knows that something important is changing.
What’s often missing in discussions about global warming is some sense of the humanistic dimensions. This is puzzling, because put bluntly, global warming is a humanistic tragedy, not an environmental tragedy. It’s not the earth that’s going to be devastated by climate change. Mass extinctions in evolutionary history are typically followed by mass speciations. New species will surely evolve to fill the niches vacated by the extinctions piling up in ever great numbers. The earth will persist—different, surely, but that’s the way things go in evolutionary time. The looming terrors of global warming—massive fires, floods, famines, with refugees in their millions fleeing too much water in Bangladesh, too little water in the Sudan—these are all tragedies in historical time, not in evolutionary time. What’s threatened by global warming is not the earth alone, but ourselves. What won’t persist is our sense of place and time--our own human histories on this earth. It’s the places we love, the relationships we cherish with the species that make their homes in those particular places, that help to make us human.
As Wallace Stegner reminded us, we see the world through our own human eyes, and it’s that human vision of the world that is under threat. John Burns, a naturalist in the northwoods of Wisconsin, writes in Paradise Lost: Climate Change in the North Woods: “The climate change scenarios currently projected for Wisconsin at the end of this century utterly boggle the mind. Conservative middle-ground scenarios show Wisconsin becoming the climatological equivalent of Arkansas, while Madison’s climate will morph into a twin of Oklahoma City….Meanwhile, the North Woods may gradually transition into an oak savannah. That’s so difficult to imagine, so close to what we can only think of as science fiction, that all of us have a great deal of trouble even conceiving of the possibility. Yet there it is, looming on the horizon like the eerie bruised sky that so often precedes a tornado. But how does one address the coming of a tornado, much less the coming of a global environmental upheaval?”[i] The potential loss is indeed difficult to comprehend, and the perspectives that historians can bring to the discussion is critical. Who wins, and who loses, when the climate changes? Who has the power to define the terms of the debates over global warming? How can humanistic perspectives help us understand people, places, and landscapes through time?
In a seminar on the past and future of the northern Great Lakes forests, we closed with a discussion of global warming. One of our seminar members was a forest planner from the Wisconsin Department of Natural Resources, whose job involves trying to plan future forest conditions for the state. She expressed her frustration at how difficult it was to manage forests given the growing uncertainties of global warming. "Our forest plans are based on history," she argued. "All our desired future conditions, all our allowable cuts, all our silvicultural treatments--they're all based on trying to restore forest types from the past, forest types that we now know are ghosts. They'll never exist again. But if we give up on trying to restore historic conditions, then what how can we manage forests? Ecologists tell us to focus on restoring processes, not historic patterns, but global warming is also changing those ecological processes. Do we just give up on hemlock? On white pine in the northern woods? On all the forests of Wisconsin?"
Ecological historians feel as if they are watching the collapse of ecosystems they spent their careers immersed in learning about, and then in learning to love. Things that to the rest of us seem trivial, or even sweet—a family camping trip with a load of firewood from home, a fishing trip with a can of earthworms for bait—spell disaster to them, because they understand the ecological history of abrupt community collapse. They know that a stick of firewood may well contain several emerald ash borers, and if just a few of those insects get out of the firewood and into the surrounding forest, that could mean 95% of our ash trees are dead within five years as the climate warms and trees lose some of their resilience to insect attacks. So much for a key component of the forest (and so much for the cultural associations local Menominee women have with ash trees, which are important for basketmaking.) The ecologists know that wiggling worms don't all get impaled on fishing hooks. A few squirm free, and havoc results in the hemlock forests, because non-native earthworms transform nitrogen cycling on the forest floor. If you walk with an ecologist in Sylvania Wilderness Area, essentially the last old growth hemlock forest left in the Great Lakes states, you can trace what the ecologists call a "killing wave" of earthworm activity. The combined stresses of insects, invasive species, and climate change may mean that the forests we now know and love are unlikely to persist and unlikely to return, at least within the historic timescales that matter to people.
What then can environmental historians do that scientists and social historians might have a hard time doing, in the face of rapid, irreversible ecological and social transformations? I hope we can do some translation: speak to the ecologists of cultural changes, and speak to other historians of ecological changes, in a language that helps both communities understand that complex relationships are being unraveled. Global warming challenges us to reexamine what history means to us, when we are changing the earth so quickly that our shared environmental histories are vanishing, possibly never to be witnessed again. Without reference to an ecological past that may no longer resemble our ecological futures, how will we learn to live responsibly in place?
[i]. John Burns, Paradise Lost, 3.