Climate Change: Who Cares?
by Jody Gibson, August 2005
Last month, Rep. Joe Barton (R-TX), Chairman of the Energy and Commerce Committee, called for an investigation of a specific study on global warming, seemingly in a last-ditch effort to stall Washington’s acceptance of the notion that human activities can cause global climate change. This appalled the scientific community, who questioned the intimidating approach and value of the investigation.
The fact is that even President Bush has acknowledged the importance of humans in affecting Earth’s climate. Why, then, would Rep. Barton call for such an investigation? Perhaps it has something to do with the fact that he has received thousands of campaign dollars from ExxonMobil1. Whatever the reason, it is obvious that many people are simply undeterred by the thought of climate change.
While “global warming” may be the phrase of choice among journalists, “climate change” is used here because any serious discussion of Earth’s climate must start from a more general perspective. Such a perspective was promoted recently by the creators of the movie “The Day After Tomorrow,” an entertaining fantasy of how we transition into the next glacial period. While it was hoped that viewers could draw the line between fact and fiction, the movie was founded on a very real issue—that of climate instability.
Records from ice caps in Greenland and Antarctica, as well as from mountain glaciers around the world, provide convincing evidence that Earth’s climate over the past 10,000 years has been abnormally stable. In fact, it may be no coincidence that agriculture developed around 10,000 years ago. Dr. Persaram Batra, a paleoclimatologist at Mount Holyoke College in Massachusetts, says that our human ancestors may have been preoccupied with finding temporary, temperate homes amidst a wildly fluctuating climate. We know that agriculture developed when grain was cultivated deliberately: people only planted seeds from the previous year’s best crop, year after year. Clearly, this type of cultivation would have been exceedingly difficult in a constantly changing environment.
The important point here is that civilization as we know it would not have been possible without a shift to a more stable climate. Now consider that many of the world’s leading climatologists are discovering that global climate can change radically within a person’s lifetime. Does this force us to wonder about the causes of climate change? It should.
Jerry Taylor, Director of Natural Resource Studies at the Cato Institute, is fond of dismissing global warming as a minor nuisance. As a strong supporter of an unregulated market, Taylor argues that the benefits of reducing greenhouse gas emissions are negligible. His argument is that an emissions reduction of X will slow the current warming trend by Y (always a very small amount); according to this simplistic cost-benefit analysis, Taylor is correct in stating that we would be better off not enforcing environmental regulations that might burden the economy.
Unfortunately, Jerry Taylor does not understand the sensitivity of Earth’s climate system. A 2003 article in Science, co-authored by prominent glaciologist and climatologist Richard Alley, reviews the facts behind abrupt climate change. Alley likens the climate system to a canoe: both external factors (e.g., water waves) and internal factors (e.g., human paddlers) can rock the boat back-and-forth, but the boat has a certain tendency to keep the paddlers upright. In the same way, Earth’s climate tends to fluctuate around a certain mean, despite occasional disturbances. In Alley’s analogy, if a paddler leans over a critical threshold, the boat will turn over completely and the paddlers will find themselves in a very unpleasant situation. In this alien state, the boat is quite stable and difficult to flip over. The lesson is that, because the climate system has critical thresholds, it would be unwise (and downright stupid) of us to continue to pump the atmosphere full of greenhouse gases, knowing that the climate is already warming.
The reason that Earth’s climate has these thresholds is because it is riddled with feedback processes, many of which involve the oceans and ice. For example, when a glacier melts, it exposes darker rock/soil to the sun, which absorbs more sunlight than ice. This heats the surface and warms the air further—a positive feedback because an initial change (warming of air) is amplified through tangential processes (melting of glacier). Fortunately, there are also many negative feedbacks that help stabilize our climate. The interplay of positive and negative feedback processes occurring over different time scales results in a highly dynamic, relatively unpredictable system.
We are justified in attempting to live free and happy lives despite an unpredictable climate. After all, even in the absence of humans the climate is capable of reverting to an unstable state, and this has occurred in the past. On the other hand, we are not justified in taking for granted our current stable climate: if we continue to ignore that global warming is a fact, and that it could lead to abrupt climate change, then we are engendering vulnerability. But just how at risk are we?
In a best-case scenario, human society will eliminate its dependence on fossil fuels, stabilize its population, and derive energy from sun, wind, and water. Such a transition will require significant amounts of time and forethought, both of which we seem to be reserving for a last-minute crisis situation. Nevertheless, even in the best-case scenario, Earth’s climate will continue to warm for the foreseeable future. If we are lucky enough, temperatures will rise only gradually and no climate threshold will be crossed. In this case, what can we expect? Professor Batra says that we are likely to see a redistribution of precipitation, increasing the frequency of droughts and floods; an increase in hurricane damage, resulting from warming of the ocean surface and an increase of coastal dwellings/businesses (including oil rigs); and an increase in mosquito-borne diseases, such as West Nile Virus. All of these will affect Houston.
Clearly, we must learn to adapt, even in the best-case scenario. The essence of adaptability is having choices, so that if we are pushed into a corner we can open up a new door (provided that we made a door in the first place). An example would be to leave land undeveloped: if changes in temperature and precipitation force farmers to relocate, they will find it much easier if fertile soil is not hidden beneath an abandoned Wal-Mart. Alternatively, farmers can practice permaculture, which, by virtue of the variety of crops grown, is more resistant to environmental stress than conventional agriculture.
The apathy of some people towards climate change may be a result of selfishness, but it is most likely a result of ignorance. In this context, dissemination of facts on climate change, or global warming, is urgent. Understanding the complexity of Earth’s climate will foster a deep respect for the forces we are currently toying with. Jerry Taylor suggests that we let the market decide when to switch away from fossil fuels, but complete deregulation hinders our predictive power, which is precisely what we want to avoid. As a society of individuals, it is possible to act in concert to achieve desired goals and avoid unpredictability. The good news is that we can begin by acting locally: please see the article, “Global Warming Gets Local,” to find out how to make a difference in Houston.
1Information on Rep. Barton is provided by the Union of Concerned Scientists.
