By Donella Meadows
–October 5, 1989–
Forward-thinking people are preparing for the greenhouse effect. Barge companies on the Mississippi are acquiring railroads in case the river becomes permanently unnavigable. Planners of Boston’s sewage treatment system are taking into account a sea-level rise from global warming. The Weyerhaeuser company is planting drought-resistant trees. The Dutch are raising their dikes.
Either this behavior is certifiably crazy, or it’s an apt assessment of the craziness of the human race as a whole — a reasoned bet that we will be stupid enough to let the greenhouse effect happen, instead of stopping it.
I’m not that much of a pessimist. I think we’re rational animals, at least when it comes to economics. The economics of the greenhouse effect are quite clear. We can’t afford it.
The Environmental Protection Agency has commissioned studies of the effects on the United States of a projected global climate change. In unemotional bureaucratic language, the report spells out unmitigated disaster.
“Wheat and corn production may … shift away from the Great Plains…. The agricultural economy may no longer be able to sustain the rural population.
“Under the driest scenario, projections for the Great Lakes region and New England are that species like eastern hemlock and sugar maple could disappear. Mature natural forests in the region could be reduced from one quarter to one half their present volumes …, with many poor sites … giving way to grassland or scrub conditions…. There will probably be disruptions and/or reductions in the availability of major forest resources — wood, water, wildlife, recreation opportunities.
“The United States could lose 30 to 70 percent of its coastal wetland with a one-meter rise in sea level…. A one-meter rise would inundate an area the size of Massachusetts. Most of these losses would be concentrated in the Southeast, particularly Louisiana and Florida.”
The EPA says that coastal areas now in 100-year floodplains would in fact be subject to storm surges on average every 15 years. Hurricanes would form more often and be stronger. Saltwater would invade groundwater aquifers and the salt-fresh interface would move higher up river mouths — endangering water supplies from Cape Cod to New York to Miami to California’s Central Valley.
Protecting coastal cities with bulkheads, levees and pumping systems would cost $30 to $100 billion. Raising barrier islands by pumping sand onto them would cost $50 to $100 billion (that would double property tax to residents of those islands, says EPA, but that’s better than losing their property altogether.) “We will probably have to gradually remove structures from much of our coastal lowlands,” says the agency. “Although this will probably not be necessary for several decades, we need to lay the groundwork today.”
The warming could increase the need for new power plants by 14 to 23 percent — on average that means four to eight new 1000 megawatt power plants in each state. That’s 200 to 400 plants. At say $2 billion apiece it would cost $400 to $800 billion for construction, not counting fuel and operating costs, or the fact that with rivers and seacoasts moving around cooling water could be hard to find.
The Great Lakes are expected to fall, shipping channels will have to be dredged, pollution will be less diluted, algae growth will increase, fish will die. Mountain snowmelts will be greater and come earlier, requiring flood protection downslope, and leaving less runoff for the summer, when it’s most needed. As precipitation patterns change, virtually every reservoir and dam in the nation will become either too large or too small.
Iowa’s corn depends not only on Midwest temperature and rainfall patterns, but on Iowa’s rich prairie loam. If good corn weather shifts north, not only will it cross into Canada, it will move onto thin, glaciated northern soils. There might not be a cornbelt at all.
Forests, prairies, wetlands will not simply pick up and move. Every kind of bird, bug, tree and soil mite will respond in its own way and at its own pace to temperature and moisture change. Pests may move faster than controlling predators, animals may move beyond sheltering habitat. Ecosystems will be taken apart and will have to come together in new combinations. Ecologists expect pest outbreaks, and extinctions. Adaptable species like English sparrows, deer, coyotes, raccoons, and many rodents will probably thrive.
Those are the possible effects on just one nation. Similar changes will be happening all over the world.
We could grin and bear these changes, spend trillions of dollars trying to adjust, and still absorb trillions of dollars worth of losses, or we could allocate a small fraction of those trillions up front to prevent the global heat trap from forming in the first place. Only a small amount of global warming is now inevitable. That amount increases every day we go on dithering.
The good news for us economically rational animals is that we know what causes the greenhouse effect, we know how to stop it, every step we need to take is worth doing in its own right, and most of them will even pay off in hard cash.
More on that next time.
Copyright Sustainability Institute 1989
