David W. Orr is the Paul Sears Distinguished Professor of Environmental Studies and Politics at Oberlin College. His new book, Down to the Wire: Confronting Climate Collapse, is an eloquent assessment of climate destabilization and an urgent call to action. In the excerpt below we learn about one challenge our government will need to address.
…the hardest tests for our Constitution and democracy are just ahead and have to do with the relationship between governance, politics, and the dramatic changes in Earth systems now under way. Human actions have set in motion a radical disruption of the biophysical systems of the planet that will undermine the human prospect, perhaps for centuries. The crucial issues will be decided by how and how well we conduct the public business in the decades and centuries ahead, and now on a planetary scale. Of the hard realities of governance ahead, five stand out.
The first challenge is that posed by climate change driven by the combustion of fossil fuels and changes in land management. The Fourth Assessment Report from the Intergovernmental Panel on Climate Change (2007), the Stern Review (Stern, 2007), the research on the effects of global change on the United States carried out by the National Science and Technology Council (2008), and other scientific evidence indicate that our future will be characterized by:
- -Rising sea levels by perhaps, eventually, as much as five to six meters or more, but no one knows for certain. What is known is that virtually everything frozen on the planet is melting much more rapidly than anyone though possible even a few years ago.
- -Higher temperatures almost everywhere, but concentrated int he northern latitudes, melting permafrost, an boreal forests turning from weak sinks for carbon into sources of carbon and methane.
- -More drought and severe heat waves, particularly in mid-continent areas.
- -Tropical diseases spreading into regions with previously temperate climates and emergence of new diseases.
- -Degradation of forests and ecosystems due to higher temperatures, drought, and changing diseases.
- -Rapid decline of marine ecosystems threatened by acidification and higher surface water temperatures.
- -Larger (and possibly more frequent) hurricanes, tornadoes and fires.
- -Loss of a significant fraction of biological diversity.
Given our past emission of heat-trapping gases, much of this is simply unavoidable. Regardless of what we do now, the Earth will warm by another half to a full degree centigrade by midcentury bringing us uncomfortably close to what many scientists believe to be the threshold of disaster. The climate system has roughly a 30-year thermal lag between the release of heat-trapping gasses and the climate-driven weather events that we experiences. Hurricane Katrina, for example, grew from a Class I storm to a Class 5 event quite possibly because of the warming effects of carbon released in the late 1970s. Similarly, the causes behind the weather headlines of the future will likely include the use of fossil fuels and land abuses decades before. We are already committed to a substantial warming of the Earth, by as much as 1.8 degrees C above pre-industrial levels.
Many credible scientists believe that we still have time to avert the worst, but not a minute to waste. No one knows for certain what a “safe” threshold of heat-trapping gases in the atmosphere might be. For hundreds of thousands and perhaps millions of years, the level of carbon dioxide did not go above ~280 parts per million (ppm), compared to the present level of 387 ppm, with another ~2+ ppm added each year. Climate scientist James Hansen has recently proposed 350 ppm CO2 as the upper boundary of safety.
We are clearly in uncharted territory. Further delay in stabilizing and reducing levels of CO2 poses what economist Nicholas Stern calls a “procrastination penalty” that will grow steadily until we eventually cross a point of no return. In other words, it will be far cheaper to act now than at some later date when effective action may no longer be possible. If the warming should occur abruptly “like the ones that are so abundant in the paleoclimate record,” we will have no time to adapt before the catastrophe strikes. And there is good reason to believe that the climate system is indeed highly sensitive to small changes: “Earth’s climate is extremely sensitive: it is capable of taking inputs that seem small to us and transforming them into outputs that seems large.”
No matter what our personal preferences, politics, or beliefs may be, as greenhouse gases accumulate in the atmosphere, temperatures will continue to rise until the Earth reaches a new equilibrium. Even were we to stop emission of CO2 today, sea levels from the thermal expansion of water and increasing mass from the melting glaciers and ice caps would change coast lines for perhaps the next thousand years. If the rate of melting is rapid or sudden, the migration inland will create hundreds of thousands, or more likely millions, of refugees-like Katrina but on a much larger scale. Unless we chose to build dikes and can afford to do so, many coastal cities will be flooded possibly within decades or by the end of the century. A majority of the millions of people who live along the Gulf Coast and eastern seaboard will have to move inland to higher ground. But we have neither the money necessary to relocate millions of people nor the infrastructure to accommodate them once moved.
The warming of the northern latitudes and oceans means many things, among which is the possibility of triggering positive feedbacks that will cause the release of large amounts of methane from permafrost and the ocean floor. As with other possible tipping points, a large release of methane to the atmosphere is a wildcard in the deck that hopefully will never be brought into play. But again the scientific evidence does not permit us to predict accurately. It is clear, however, that the government is ill prepared to handle the social, economic, and political disruption to which we are now committed, to say nothing of the effects of more rapid changes…