Earth in Human Hands Page 15

  CFCs were once hailed as an environmentally responsible alternative. Developed as a more benign kind of refrigerant than the toxic and stinky molecules they supplanted, such as ammonia and sulfur dioxide, they seemed like an important breakthrough for health and safety. Their use was quite clever—but not quite clever enough. The road to planetary hell is paved with ingenious solutions and good intentions. Scientists trumpeted the fact that these gases were completely safe because they are chemically inert, meaning they don’t react with anything. This is true—at least in the troposphere, the turbulent bottom part of the atmosphere where we live*—but nobody had thought through every possible consequence of introducing them into the environment in large quantities. We never can. When these gases eventually leaked up into the stratosphere, twenty miles up, they went through a transformation driven by the intense solar ultraviolet light up there. Energetic photons readily split off chlorine atoms (the first C in CFC). Once liberated, this chlorine started doing what Venus taught us chlorine does: attacking and destroying ozone.

  Nobody had worried about the effects of ultraviolet light on CFCs. When we introduce a new product, we don’t usually ask what will happen to it under intense ultraviolet irradiation. Why ask such a hypothetical question when we don’t live on a planet with such a dangerous flux? We don’t have to worry too much about the effect of UV radiation on our household and industrial products (not to mention our crops and our skin) because we have an ozone layer that shields the lower atmosphere and surface from solar ultraviolet rays. Yet what if that protection were suddenly being eroded?

  Frank Sherwood (Sherry) Rowland and Mario Molina from the University of California put all this together and showed that the chlorine we were venting high into the sky could indeed be destroying Earth’s ozone shield (the work for which, along with Paul Crutzen, they won the Nobel Prize in 1995). Subsequent ground-based, airborne, and satellite observations confirmed that Earth’s ozone was indeed in decline, most notably in the seasonal opening of a dangerous “ozone hole” over the southern high latitudes. This was a frightening discovery because this powerful radiation not only splits up CO2 and CFCs, it also damages the fragile organic molecules that compose our cells, and in particular wreaks havoc with DNA, causing mutations and cancer.

  Had we not started exploring Venus in the 1960s and ’70s, we would certainly have noticed what was happening to the ozone, eventually. Still, it’s a good thing we figured this out when we did. If you want to see what a planet with no ozone layer is like, take a look at Mars, where the surface is bathed in deadly ultraviolet radiation. Billions of years ago, back before Earth had enough oxygen to make ozone, all life was confined to the ocean, because the land was sterilized by Mars-like solar radiation. Earth’s stratospheric ozone screen, a by-product of the Great Oxygenation Event more than two billion years ago, made the land surface habitable. Without knowing it, we had recently started reversing this. We had been inadvertently tinkering with one of Earth’s basic life-support mechanisms.

  This is a classic example of unintended consequences. What gets you is the “unknown unknowns,” and that’s why we need as much out-of-the-box, off-the-planet perspective as we can gain. As we increasingly perturb our world, we need to educate ourselves broadly about all aspects of planetary systems. This often means following our curiosity beyond what seems immediately practical, filling in gaps in our knowledge of planetary behavior. The more we know, the less likely we are to make dumb mistakes. In this case, the insights gained from our efforts simply to understand weird chemistry in the uppermost air of Venus contributed directly to our discovery of something dangerous happening to the ozone of Earth.

  We did not intend to destroy the ozone layer, any more than the cyanobacteria intended to create it in the first place. Unlike them, however, we had the ability to see what we had begun, and to choose not to finish it. This ozone story has a happy ending. The wide recognition of the problem in the 1980s prompted global discussions. Solutions were identified, replacement products that could serve the same purposes without the dangerous side-effects. Agreements were made. Treaties were signed. The Vienna Convention for the Protection of the Ozone Layer entered into force in 1988, and was followed by the stronger Montreal Protocol on Substances That Deplete the Ozone Layer in 1989, which included legally binding reduction targets for the use of CFCs. And guess what? It’s working. Despite some defiance, lawbreaking, and profiteering, by and large the protocol is holding, the emissions of CFCs have leveled off, and the ozone hole is on its way to recovery. There is no quick fix because the inherent timescale of the problem is long. It takes fifty to one hundred years for a CFC molecule to diffuse into the stratosphere and get broken down by sunlight. It takes a roughly equivalent time for the natural chemical cycles in the stratosphere to repair the damage. Vigilance is required. Yet, so far, so good. The ozone hole is still there, but it is no longer increasing in size. Projections show it on schedule to being fully repaired by mid-twenty-first century.

  We should feel good about this, and what it implies about us. We recognized the danger, worked the problem, and are well on our way to fixing it. So while the ozone story began as an example of the third kind of planetary change, inadvertent catastrophe, it became an example of something else: an intentional planetary change—what I call a planetary change of the fourth kind.

  Self-Control

  Planet Earth is being rapidly remade by forces it has never previously encountered. The explosive expansion of human numbers and technological imprint is transforming the environment of every species, including that of Homo sapiens. Are we active participants in this transformation? It depends on what we mean by “we” and “active.” Certainly we’re not just spectators, but considered as a global entity, are we, humanity, even smart and in control enough to be considered a perpetrator? Or are we more like a partially awake automaton, slave to our biological imperatives to grow and compete and grow some more, even when we’re overfilling our container like a root-bound plant? Is there even any kind of a coherent “we” who is responsible for our behavior on a global level? Not obviously, not in the same clear-cut sense as when you can ask, “Whose idea was this?” or “Who made a mess out of this kitchen?” or “Who shot J. R.?” and identify a culprit. Certainly there is no individual who decided to do all this, and it’s not as if we all got together and decided to make these alterations to our world. Rather, we have now attained global impact without any sense of global control: the Anthropocene dilemma.

  Here, I find it useful to point out the distinction between cleverness and wisdom. Cleverness is the ability to solve problems through invention and innovation. We’ve got that in spades. Wisdom is the ability to apply experience, awareness of context, and prior knowledge of consequences, and fold all that into action. There, we seem to be more challenged. Even to the extent (which is rapidly growing) that we are aware of our global influence, our capability to apply this knowledge and change course, even in the interest of self-preservation, is not clear. We’re finding that, for now, our great cleverness has outstripped our wisdom.

  We could also look at this in terms of systems theory. As I describe earlier in this book when discussing planetary climate evolution, the behavior of complex systems with many interacting, changing parts is often controlled by feedbacks, positive ones acting as destabilizing forces and negative ones acting to increase stability. An example I use is the positive feedback that long ago led to a runaway greenhouse on Venus, dooming the oceans and the once more moderate climate of our sister planet. As organisms, we can sense changes in our surroundings and in ourselves as we interact with our environment, and modify our actions accordingly. When we do so, we generally apply negative feedbacks to maintain equilibrium or stay on course in some way. In our daily lives we do this literally all the time. Any action that involves any kind of balance or finesse usually involves a lot of this, much of it unconscious, on autopilot. When you walk across a room, you are constantly sensing how you stand
with respect to your center of gravity, and adjusting accordingly without needing to realize what you’re doing. Driving down a road, you sense if you are getting too close to the center line or the curb, or to the car in front, and without even being aware of it, you nudge yourself toward safety. The autopilot comparison is apt, by the way, because when we design control systems for aircraft or spacecraft, we’re mimicking an aspect of our own cognitive capacities. Machines with sensors, controls, circuits, and algorithms do what we do: sense their environment and make adjustments to maintain some desired condition. Negative feedback also describes conscious self-control. When you realize you are getting a little tipsy, you can (I hope) think to yourself, “I guess I’ve had enough,” and moderate your intake.

  One thing we humans can also do is intentionally choose to put functions on autopilot that were once under conscious control. We do this when we learn to operate machinery or software or to master a musical instrument. I’ve been playing guitar since the fifth grade, and while I’m no Hendrix, I’m not a beginner. When I was just getting started and wanted to jam with someone, I would have to ask what key they were playing in, then think, “B minor? Okay, move hand to seventh fret and play within this pattern for a minor key.” Now I can hear the song and watch my fingers move to the right place and start doing the right thing. When you are first learning to drive, you actually need to think to yourself, “Uh-oh, I am going too fast. I’d better step on the brake”—which is why student drivers should be given wide berth. When you’re more experienced, you just sense you are speeding, and your foot applies pressure. You develop reflexes to act more quickly, circumventing the thought process.

  Enacting such control consciously or unconsciously merely requires an ability to sense your surroundings, including the effects of your own activity, and to develop mechanisms to apply this information as input to modify your continued activity. This is a fundamental property of a cognitive creature, but for the most part in our global activities, we do not have this basic ability to temper our actions with compensating reactions. In this way, collectively, we exhibit less of a certain hallmark of intelligence than does an infant learning to walk. As our ability to change the world increases, so does our potential to create dangerous positive feedbacks, which can lead to runaway changes in the environment. What about the potential for cultivating habits and mechanisms for negative feedbacks that would counter these? Can we, global humanity, sense our environment and act on that input?

  There are certainly some negative feedbacks operating today in our economy and our global technosphere. The “law” of supply and demand is one example. This resembles the unconscious feedbacks undertaken by an individual, but it is weak at best, prone to oscillation and instability. To control our capacity for runaway global behaviors, an important first step is wide awareness of global consequences. Knowing what we are doing is necessary, but is it sufficient? Without strong mechanisms to apply such knowledge as input to future decisions, negative, stabilizing feedbacks cannot compete with the positive, destabilizing ones. Many of our activities are currently creating a pattern, seen in the graphs just shown, of exponential, or runaway, change. We’re sending all the indicators off the charts. Such a pattern is characteristic of a complex system dominated by positive feedbacks. This is a precarious situation. It can’t last.

  Yet the existence and application of world-changing technology need not lead to runaway states or wild swings in environment. The solution is to increase our capacity for planetary changes of the fourth kind: intentional changes.

  What do I mean by intentional planetary changes? Global-scale changes that result from actions undertaken with forethought by an intelligent technological species aware of its actions and their consequences. Yes, these are loaded terms. Here I actually mean to suggest a reconsideration of what we mean by “intelligent life,” one that I find useful for discussing the role of life and mind in planetary evolution (and also for the I in SETI, as I will discuss in chapter 6). Because when some form of life gets to the point where it has this capacity to change the world on purpose, it can take on a powerful new role in the life of the planet. It’s fine and customary to define intelligence as a kind of neuronal activity or capacity for logic or abstract thought or in terms of the relationship between a creature with a nervous system and its environment. Yet here we’re trying to understand a stage in the development of a biosphere, when an unprecedented kind of phenomenon, a new force in planetary evolution, starts to manifest itself and may or may not become a stable factor in the long-term evolution of a planet. We could then consider classifying intelligence by the effect it has on planetary evolution. There is a kind of cognitive activity that results in rampant, unchecked, unplanned global change of the kind we’re seeing today, and there is another level, what we might call true intelligence, or planetary intelligence, of more globally coordinated cognitive activity, that can result in more stabilizing behavior.

  As I will discuss further, when we think of looking for the signs of intelligent civilizations elsewhere in the universe, this is the only kind of intelligence that it makes sense to search for. Such a definition also leaves it undetermined whether intelligent life has arrived on Earth. That’s part of why I like it. It is not so self-congratulatory and does not imply that we are some kind of standard for intelligence in the universe. It gives us something to try for.

  4

  PLANETARY CHANGES OF THE FOURTH KIND

  What is the use of a house if you haven’t got a tolerable planet to put it on?

  —Henry David Thoreau

  Changing the World on Purpose

  Some will reflexively feel that any attempt to purposefully change Earth is a bad idea, that the very notion is hubristic and foolish. People intuitively love the natural and suspect the artificial. It’s not nice to fool Mother Nature, and it’s painfully easy to come up with examples of vain human attempts to control or outsmart nature that have backfired badly. From this you might conclude that the best course for us is to take a “hands off” approach to our planet, but at this point even agreeing to take our hands off would in itself be a huge intentional planetary change. We no longer have the option to avoid choices about how, collectively, globally, to apply Earth-changing technology. We have to choose, and “None of the above” is not a possibility. Even if you were the most radical green who ever lived, and you insisted that we must instantly shut down every car and factory, you would be advocating for conscious intervention in planetary functioning, and therefore for a massive planetary change of the fourth kind.

  This includes any collective corrective measures we take to fix environmental problems of our own making. A global agreement to stop a change of the third kind is a change of the fourth kind. This is true whether it comes about through a “top-down” global covenant or a successful grass-roots movement to change mass behavior. So, if purposeful global change is ill-advised, then any appeal for global action on climate issues is wrong-headed. Cynical voices will object that a vision of world-changing technology applied collectively, thoughtfully, and carefully, with wisdom, is utopian, futile, or impossible. Yet we’ve already seen that it is not. I’m describing something that obviously does not require a perfect, unified global society, because it is already occurring even on our fractious, troubled orb. The ozone recovery is an excellent and hopeful example. Broad-based curiosity-driven science allowed us to recognize the problem. We saw what we were doing, and this incited a global conversation that, within a few years, led to effective action. Now the ozone hole is on track to being just a memory by about 2050.

  Yes, there are uglier wrinkles in the ozone story. As a scientific consensus emerged, it was met with a great deal of resistance. The manufacturers of CFCs mounted a concerted disinformation campaign, which included hiring scientific “experts” to cloud the issue and lobbyists to insist that more research was needed before any action could be taken. The scientific evidence was called a hoax, and many smart people who fancied themselve
s skeptics were sucked in by an orchestrated public backlash.

  A frightening turning point came in 1985, when the Antarctic ozone hole was discovered to be already well developed and growing. The situation was worse than had been predicted. Soon the DuPont Corporation, the biggest manufacturer of CFCs, which had led the well-funded denial campaign, did an about-face and joined in calls for a regulated global phase-out. Why did they do this? They didn’t suddenly abandon the profit motive in favor of global responsibility. They realized that a phase-out was inevitable and hoped to influence the terms of the treaty to make it gradual enough to preserve profits. It helped that they had by then patented the important replacement gases and stood to profit further. But, so what? The science ultimately gained widespread acceptance. Forward-looking corporations saw the writing on the wall and realized that the smart money would follow the quest for environmentally safe alternatives.1 A further wrinkle is that some of those replacement gases, substituted for CFCs, now turn out to be very strong greenhouse gases, so introducing them fixes one problem but exacerbates another. This demonstrates that, at our current level of knowledge (or lack thereof), even considered and constructive global actions are still not immune from unintended consequences. So these gases will in turn be phased out in favor of others. Ozone recovery is not a done deal—we have to stay on track, but there is no real reason at this point to doubt that we will.