In the last post, I mentioned that one contemporary application of ecology is to the management of complex systems. A complex ecological system is characterized by changes that are predictable in a general way—that is, as a trend or tendency—but where prediction is difficult or even impossible in single specific cases. Under such conditions, where general disturbances and perturbations are highly probable, but just when and where is difficult to predict, managing for resiliency appears to be the best sustainability strategy. These ideas must seem very abstract to the general reader. A chance encounter with an interview on National Public Radio a few days ago (July 25, 2011) gives me an opportunity to try to make these ideas more concrete.
The subject of the interview was climate change. Now climate (and weather) is a good example of just such a complex system that I’m writing about. So, by implication, is the ecological system that is a music culture, but for now let’s confine ourselves to something that “everyone talks about but nobody can do anything about” — climate and weather. In fact, of course, we must do something to manage it if we are going to lessen the horrific consequences of climate change in the coming centuries. We have a chance to decrease the amount of climate change due to carbon emissions and greenhouse gases; and we have a chance to manage our adaptations to whatever climate change occurs, instead of just submitting to it.
Weather, as everyone knows, is an example where predictions are “probable” and “likely” rather than certain; and where accuracy varies according to how soon the event is to occur (the sooner, the more accurate) and how local the observations are. You look up at the sky and see a storm approach; soon you hear thunder. Rain is very likely within the next five or ten minutes and you’d best close your windows (unless you live an air-conditioned life). You consult the daily weather report that says a thunderstorm will occur; nowadays the forecasters use mathematical models to predict the storm accurately, in a given location, to the hour, but this proves less accurate than direct and immediate observation. And yet it has value for planning. Forecasters predict even more generally that there is so much percentage chance of precipitation during a given day. And most people are aware that the longer range forecasts are less accurate than the short range.
What was interesting to me about this interview was how and why the interviewer and the expert talked past each other. The interviewer was Terry Gross, an experienced interviewer who has spoken with scientists, social scientists, writers and artists on her NPR show “Fresh Air” for decades. The scientist was climatologist Heidi Cullen, a writer and lecturer on climate change, a professor at Princeton and author of the book, The Weather of the Future. The questions Gross asked were, I think, questions that most people are asking about climate change and specific weather events. Gross asked the expert whether climate change was responsible for this summer’s unusually hot weather, or for last spring’s bad floods and tornadoes. She asked whether there might be an upside to climate change for people in places like Philadelphia, her home town, for if it got warmer then there could be less snowfall and because she didn’t care very much for snow, that would be a good thing.
Cullen’s replies seemed evasive. Yes, she said, human beings’ activities in the past couple of centuries, notably their release of fossil fuels into the atmosphere, have certainly caused climate change, and with this climate change certainly comes more extremes in weather—more hurricanes, more severe rainstorms, hotter heat, colder cold, more flooding, and we had better be prepared for it. But Gross wanted to know with certainty, or at least a reasonable amount of it, if this year’s unusual floods in the midwest, and tornadoes in the southwest, and the extreme heat that settled in the midwest and east this past month, breaking all kinds of records, were the result of climate change—or were they just instances of the “normal” kinds of weather extremes, the notable ones that have occurred throughout human history? And Cullen could not answer to her satisfaction.
Why not? Again, because climate and weather are complex systems, in which predictions are probabilities, not simply cause and effect. Geologists predict that there will be a big earthquake in California in the next fifty years, but they can’t say just where although they predict probabilities based on fault lines. Nor can they predict just when. The same with climate change. Scientists know that human beings have changed the climate by burning fossil fuels with gases released into the atmosphere that have caused global warming and trapped more moisture. Scientists know that as a result, on average, severe weather events will increase in number: there will be stronger storms, more severe floods, hotter heat waves, colder cold waves, more damaging tornados, heavier snowfalls. Weather extremes will be greater. What they can’t say is that this one particular extreme weather event certainly was caused by climate change and that without climate change it would not have occurred.
Gross found Cullen’s answers frustrating. Yes, Cullen said, in the changing climate Philadelphia was going to get warmer; but Gross’s hope for less snow would not necessarily be realized, for climate change was circulating more moisture in the atmosphere, with stronger storms as a result. After all, as long as the temperature was below freezing, this moisture would come to earth in Philadelphia as snow, and there might be more of it. Gross was not happy to hear her hopes for less snowy winters in Philadelphia dashed, and less happy still to live in the uncertainty that they might even be snowier. She turned to another subject: early spring. Surely there was an upside to the fact that spring seems to be coming earlier these days; she hates winter. Now the flowers are blooming sooner, and the grass is green sooner, and she can put away her winter clothing sooner and be more comfortable. Well, Cullen replied, the early warming is also responsible for more rapid ice melt in the mountains; the ground cannot absorb it so quickly and it results in floods like the ones that have occurred in the past decade. The implication was that early bloom and sooner put-away winter clothing was a trivial gain compared to the losses from catastrophic floods.
What was interesting to me in this dialogue was not so much Gross’s inexperience with the kind of climate thinking Cullen engaged in on a daily basis, as her inability to put her mind into Cullen’s framework of complex systems. It is easy to say that in Philadelphia Gross experiences the natural world as someone who lives and works in a city, probably indoors most of the time, where climate is controlled, and that is why there was such a disconnect. But I think there is more to it than that. Gross is used to thinking about weather and climate—and many other things—in terms of direct causes and effects. In fact, of course, that is how we experience the world from one moment to the next. We type on a key and expect to see the letter appear on the screen. We turn on the gas on the stove and expect to see the flame and feel the heat. We turn the key in the ignition and expect the car to start, even though we know that many things have to be set in operation, whether in the computer, the stove, or the automobile.
Complex systems thinking is something we engage in, if we do so at all, when our normal understanding of cause and effect breaks down. The appliance doesn’t operate as it should—why not? It could be this, it could be that; we “troubleshoot” and suddenly become aware of the many things that could be causing the problem, some individual and some in combination; and we imagine that there might be other causes that we don’t know. This is not an easy way to think. I know some people who are good at it, and some for whom it is as foreign a country as Mars. But it is the kind of thinking that is involved in managing for sustainability, whether we are working out strategies for resiliency, or diversity, or anything else; and whether we are attempting to manage the natural world, social organizations, household or national economies, or music cultures.