Have you ever had that micro-macro sensation in which you feel yourself to be a tiny organism interacting with some infinitely greater being? I experienced something similar upon reading The Ages of Gaia: A Biography of Our Living Earth by James Lovelock (1988, W. W. Norton). Lovelock contends that just as countless organisms sustain human life, so have living things transformed our planet from an inert chemical ball into a self-sustaining organism. This view, instead of evoking the expected feeling of insignificance, left me mulling over the concept of being a child of mother earth—Gaia, as the Greeks called her.
For almost 20 years, Lovelock has theorized that our earth, water and air have been changed in very specific ways by the presence of life. But his most scientifically heretical suggestion has been that these basic elements have been regulated by evolving life-forms. In other words, they did not just adapt to their surroundings, as disciples of Darwin believed, but remade them.
For example, when Archean life began about 4 billion years ago, the sun was 30% cooler than it is today. Yet the average temperature of the earth's surface has remained within the critical life-supporting range of 50° to 68°F—even during the ice ages—thanks to a hundredfold drop in the carbon dioxide level, which offset the warming of the sun by reducing the atmosphere's capacity to hold heat. In other words, the earth has managed to maintain a constant temperature, much as mammalian bodies do.
Likewise, about 2 billion years ago, ancient plants began using photosynthesis to harness the sun's energy, producing oxygen as a by-product and eventually creating an atmosphere in which many new life-forms could evolve. And, despite volcanic eruptions, meteor impacts and species extinctions—which would, as Lovelock puts it, "make total nuclear war seem, by comparison, as trivial as a summer breeze"—the planet's evolving photosynthesizers have held oxygen at an ideal 21% for the past 200 million years. Should this level vary by a few percentage points either up or down, life as we know it would end.
In another example, the oceans' salt content, 3.5% by weight, remains roughly constant despite continental runoff that dumps more than 500 megatons of salt into the water each year.
An "interdisciplinary wanderer," James Lovelock holds a Ph.D. in medicine from the University of London but is generally considered to be a biologist. He has also served as a professor of chemistry at Houston's Baylor College of Medicine and as visiting professor of cybernetics at England's University of Reading, and he was elected president of the Marine Biological Association of the United Kingdom. Above all, he's an inventor; his many patents support both his family and his personal scientific research, most of which he conducts without assistance in a country cottage in southwestern England. (The data gathered using his palm-sized electron capture detector, developed in 1957, substantiated the threat of pesticides as detailed by Rachel Carson in Silent Spring, and Lovelock, using this same detector, was the first to demonstrate that chlorofluorocarbons were accumulating worldwide.)
In fact, it was while working on tests for NASA to detect life on Mars that the British scientist created his "living earth" theory. He argued that no soil-sampling probes of the planet were necessary, since scientists could detect the existence of organic activity simply by looking in the Martian atmosphere for concentrations of gases that can exist only if they are maintained by living organisms. On the earth, he explained, life uses the gaseous layer encircling it both as a source of raw materials and as a repository for waste. This kind of interaction has kept our atmosphere from reaching a state of equilibrium—unlike the stable-state atmospheres on Mars and Venus, which are made up almost entirely of carbon dioxide.
Until recently, however, most scientists either ignored the Gaia hypothesis or criticized it as being teleological, claiming it presumes an ultimate purpose that "guides" organisms to behave in ways that help the aggregate of life. Lovelock, however, has always maintained that a seemingly intelligent global system could arise automatically from the planet's mindless struggle for survival.
Gaia, instead, has been embraced by New Ag environmentalists, for whom it implies a unification of life—prompting Lovelock to note that "Gaia may turn out to be the first religion to have a testable scientific theory embedded within it"—and, conversely, by industrial polluters, who argue that the earth's living system can take care of any deleterious materials. Lovelock says that Gaia, through the natural functions of species and environment, can compensate for our unrelenting destruction of the environment, but, he reminds us, while Gaia will survive, humans may not!
"We are ourselves a product of a planetary catastrophe," he writes. "Could it be that we are unwittingly precipitating another punctuation that will alter the environment to suit our successors?"
When he's asked how Homosapiens can avoid such a fate, he replies, "It's personal action that counts. Any biological activation starts with a single organism."
Through "personal action" of his own, in addition to giving both scientists and ordinary people a new-old way of looking at the earth, Lovelock and his family have planted more than 20,000 trees.
Earlier this year I was given the opportunity to interview James Lovelock on behalf of MOTHER EARTH NEWS. Having read Lovelock's books and several reviews of his work and ideas, I was delighted to learn more about the man himself and to question him on his prognosis for the future of the planet. Here is an abbreviated report of our conversation.
MOTHER: How have you maintained your interdisciplinary view at a time when most other scientists are becoming increasingly specialized?
Lovelock: I suppose I've always been a loner, tending to develop on my own. I didn't like education one bit and was able to get away with a minimum of what I call "being taught at." I wouldn't recommend that for everybody. I don't want to be prescriptive, but it certainly suited me.
MOTHER: Is this loner attitude the secret of your success as an independent scientist—what you yourself have called a rare and endangered species?
Lovelock: The only secret I know for leading a successful life as an independent scientist is just simply never to do anything that's dull and uninteresting. Only do things that interest you maximally. If you do spend most of your time on dull and uninteresting things, you rapidly dry up. You're in competition with everybody else, too. But if you do only interesting things, you're bound to break new ground; you have to invent new instruments to find the answers to your new research. It doesn't take long before people want to know where they can get one of those instruments or how they can get in on the new field of study. That's the secret. It's worked for me for 27 years, so I don't think there can be much wrong with it.
MOTHER: But doesn't the scientific community still consider you a bit of a heretic?
Lovelock: Well, no. Without wishing to appear bigheaded, I think I can say that the Gaia theory is a rather large notion—larger than the theory of plate tectonics, for example. It took 30 or 40 years for plate tectonics to be accepted, and even 15 to 20 years after the theory was first published—which is roughly where Gaia is now—everybody still thought it was nonsense. It took a long time to finally convince the geologic fraternity. Now, of course, plate tectonics is accepted, and I also think Gaia's been doing exceedingly well scientifically.
MOTHER: You've said that scientists intuit a theory and then try to prove that intuition. Hasn't the concept of a living earth mother been with us for ages?
Lovelock: Of course it has. At one time everybody viewed the earth as a living entity, but this concept was lost in the 19th century. It was the exploration of space that forced us to look at the planetary picture again.
You have to realize that in the 19th century science became exceedingly professional and specialized. It was inevitable. Up till then the data bank about the earth was very limited, so as the century progressed and exploring scientists brought back new data, everybody got confused. It was so easy to forget the big picture in the rush to classify all this new information. Science split up into fragments, and professors had their own little baronies with their own arcane languages that nobody else could understand. For example, they got deeply entangled in the evolution of the species and thought Darwin's theory covered everything. It is comprehensive, and in no way would I want to contradict or fail to recognize the greatness of his contribution, but how could you expect that theory to cover everything when the data wasn't available, even to him?
It's simply not enough to consider the evolution of the species independently of the evolution of the physical and chemical environment. The evolution of the physical and chemical environment and the evolution of the species combine into a unified process from which self-regulation emerges. That's the modern definition of Gaia: an evolutionary process leading to selfregulation.
MOTHER: If our planet, Gaia, is an evolutionary, self-regulating system, then it could be considered a life-form, couldn't it?
Lovelock: I think it might help to compare the earth to a giant redwood tree that weighs 2,000 tons. Most people, when asked what's the biggest form of life, say it's a whale. But a whale is small when compared with a red wood. A living redwood tree is actually 97% dead. All of the wood in the middle is dead; all of the bark outside is dead; there's just a thin skin of living tissue around the circumference. But all of the dead material is a direct product of life or has been processed through many organisms. This is very like the earth. There's a thin skin of living tissue around the outside, of which both the trees and we humans are a part. All the rocks beneath our feet and the air above us are dead. But all the rock and all the atmosphere, except the rare gases, have been greatly modified by the presence of life.
MOTHER: Why does the scientific community have such a hard time with that concept?
Lovelock: You've got to remember that most academics have an enormous vested interest in the status quo. They write textbooks, teach courses and all the rest. If some outside person like me comes along with something that's going to turn the whole thing topsy-turvy and require them to rewrite their textbooks and reorganize their course work, they're not going to like it one bit. They're going to react strongly, and they're beginning to do that. At first, they thought they could ignore Gaia, and it would just go away—thought it was a New Age freak-out thing. But quite clearly that won't work, because its main advocates now come from the fields of climatology and meteorology—disciplines whose business it is to measure the world. These people have to support the Gaia hypothesis because every day they must face the hard facts of environmental problems. Scientists in many other fields, like biology, do most of their research in dark rooms in universities, peering down microscopes, and they seldom see the real world at all. Some still think Gaia will go away.
MOTHER: But the World Meteorological Office recently awarded you and three colleagues a prize for work that backs up the Gaia theory. Could you tell us about that?
Lovelock: They recognized the importance of the discovery. The WMO feels it significantly advances the understanding of climate.
You see, as a result of Gaia, I went out looking for dimethyl sulfide, an emission from the ocean that we now suspect accounts for 80 to 90% of the particles necessary for cloud formation over the open oceans. There was no way to get funding for this; it was so contrary to conventional wisdom that it was generally regarded as a waste of time. Nevertheless, I found and measured the emission and published a paper on it in Nature magazine in 1973. The paper fell like a lead balloon, and nobody took any notice until 1980, when a German scientist, Andy Andreae, mounted a major expedition over all the world's oceans, repeated my measurements and confirmed them. He published this in detail in many papers. When Andreae received the prize on behalf of the four of us, he stated that the work would never have been done but for Gaia.
MOTHER: But what does this discovery mean to the climate and to us?
Lovelock: There were no known cloud condensation nuclei out over the oceans, so there supposedly was nothing on which the cloud droplets could condense, and yet there were clouds there. No one knew why. But dimethyl sulfide oxidizes in the atmosphere and is converted to sulfuric acid and methanesulfonic acids. This produces ideal cloud condensation nuclei, since the tiny, strongly acidic droplets that form encourage water condensation. And this dimethyl sulfide comes entirely from algae blooms on the ocean's surface and from nowhere else. Here we had, at long last, a potential Gaian feedback system, because the algae can bloom in a matter of days, producing a true fast-reaction climate regulator. It's still early, so we don't know the full details of the feedback yet. However, from the results of NASA's satellite investigations—and also from analyzing ships' plumes as aircraft fly through them and inject sulfur dioxide, an occurrence that mimics the effect of algae emissions—we do know all predictions in our Nature paper were right to a percent or so. They were obtained by a straightforward geophysical method. I think that's why we got the prize, because our research was so completely controlled, and scientists like good predictions. The prize also established Gaia as a scientific theory more strongly than anything else so far. But don't forget, almost nobody is working on Gaia—certainly nobody working full-time—and until very recently there was no funding. We're talking about investigations conducted part-time by, initially at least, only four people.
MOTHER: How does this feedback system work?
Lovelock: It's very strange. There are many species of unicellular organisms living in the ocean, and they are some of the most important organisms on earth. They take carbon dioxide out of the atmosphere and deposit it as an ooze that eventually becomes limestone. They also probably are responsible for the deposition of quite a lot of carbon—mostly it's just diffuse carbon—some of which becomes petroleum deposits. The burial of carbon in the sediments is the only source of oxygen. These organisms are the key, then, to the production of two gases, oxygen and carbon dioxide, and it looks as if they're the key to regulating climate, too—in their ability not only to pump down carbon dioxide but also to produce the gas dimethyl sulfide, which controls clouds.
The production of dimethyl sulfide by unicellular organisms makes a rather funny story. Any organism living in the ocean has a salt problem, because the ocean is too salty for life. A big creature such as a whale or a fish has its own pumping system to keep its interior salt concentration the same as that of humans. It pumps water in and salt out so as to keep the proper electrolyte balance. That's easy for a big multicellular organism, especially if it has a relatively impermeable skin. But it you're just a unicellular creature with a very small volume-to-surface ratio, it's impossible to have a pump big enough to do the job. The trick they learned was to form an interior chemical salt called betaine, which is harmless. In the chemist's jargon it's a charged neutral salt that acts like regular salt in some ways, but it doesn't have damaging effect on cell membranes. Some land plants, such as beetroot, are full of charged neutral nitrogen betaine that enable them to grow well in salty ground. Out in the ocean, however, nitrogen is extremely scarce, so the algae learned to produce a sulfur betaine. This compound is easily made by ocean organisms, because there's lots of sulfur in the water that is not claimed for an other particular purpose. The organism builds up a concentration of betaine inside the cell to balance the osmotic pressure of salt on the outside. Therefore, a relatively small pump can keep it quite happy. Then, when one of these cells dies or is eaten, the betaine escapes into the seawater. Enzymic processes in the guts of other organisms, or just simple inorganic reactions, cause it to decompose, converting it into dimethyl sulfide.
In the large Gaian sea, a creature will not produce something beneficial to the environment unless it benefits from the feedback. So what's in it for the algae? The benefit is this: Once the dimethyl sulfide gets into the atmosphere above the ocean, and clouds form, the condensation of water vapor onto the droplets releases 600 calories for every gram of water deposited. That's a huge amount of heat—an enormous energy release. As a result, up goes a big updraft of cloud, and thunderheads form, producing a tropical thunderstorm or even a hurricane. Wind is drawn underneath the clouds, and this stirs up the sea more and more.
Now in the summertime, the top layer of the ocean is denuded of nutrients—they are consumed by sea life, the upper water stays warm, and nothing mixes up from below. Then winds stir the oceans and bring up nutrients from below. This feeds the algae, so they have a strong vested interest in sustaining this process that they accidentally initiated.
We don't know yet what the global climate feedback is, but wind is the link. What's so exciting is that measurements taken by others over the last 10 years have shown three things: First, algal growth in the Pacific has increased by 100% . Second, cloud cover over the oceans has increased worldwide. And, third, there is more wind.
MOTHER: Is this a Gaian response to the greenhouse effect?
Lovelock: It's probably a system response to the carbon dioxide buildup, which might be feeding the algae. Something has caused the algal population to increase. It's unlikely that it's a response to a rising temperature, because there hasn't been enough of a rise to account for it. But there is a response under way. It's a tangled story that's going to keep scientists very happy working on it for a a long time.
MOTHER: Have any other feedback loops come to light?
Lovelock: Not as big as the one I've just mentioned. However, there's growing evidence now that the carbon dioxide cycle is regulated by plants, but not, as is commonly thought, by plants taking carbon dioxide from the earth. That doesn't remove it, because animals eat the plants and put it all back again. That's a do-nothing cycle that just goes round and round.
The way plants operate is twofold: In the terrestrial biota, the trees—particularly the temperate-region trees—during their growth, deposit enormous volumes of carbon in their roots. A redwood tree may deposit as much as 2,000 tons of carbon underground. Now when that tree dies, all of that carbon oxidizes and releases carbon dioxide down in the soil right next to the rocks. The rate of reaction of carbon dioxide with calcium silicate (the weathering of crustal rock) is increased by a factor of 30 by the presence of trees; the plants are pumping carbon dioxide out of the atmosphere by forcing it to react to the rock, which it would not do otherwise. If you analyze the soil, you find that there is about 30 times more carbon dioxide in the soil than is in the atmosphere above, which shows how strongly and how powerfully it's pumped. A 30-fold positive gradient could not be reached by diffusion; it would be the other way around: There would be less in the soil, not more, if it were simply diffused. So we have the proof that a major pump exists. That's why carbon dioxide is a trace gas on earth, whereas on other planets it's the major gas in the atmosphere.
MOTHER: So as we lose trees, we are losing these major carbon dioxide pumps.
Lovelock: That's right. Of course, the sea algae that I mentioned earlier facilitate this cycle. Otherwise, carbon dioxide would pile up in the oceans as calcium bicarbonate, which is what is washed down through the rivers. It doesn't pile up, because the algae deposit it as limestone. They're a part of the conveyor belt—a very key one. That loop is fairly well established.
MOTHER: In your book The Ages of Gaia, you point out that there are two perspectives on such problems as the greenhouse effect, acid rain and the depletion of the ozone layer. One is the human perspective, and the second is the Gaian perspective. From the Gaian perspective, what may be important to us may not be important to Gaia. In fact, you've noted that Gaia is no doting mother, and that if a species screws up, she eliminates it with all the feeling of the microbrain in an ICBM. To Gaia, humans may not be as important as algae.
Lovelock: I think we're important to Gaia because we have the capability of initiating the major perturbation that destroys the present system. That makes us an important species in the same way that Genghis Khan or Hitler was important in human history. One never knows when the final perturbation will come. It's more than possible that that's what happened on Mars—that there was life there initially, and it was destroyed. There's adequate evidence, such as great river valleys and floodplains, to indicate that there was water flowing on Mars. If so, Mars must have been warm at a time when the sun was even cooler than it is now, which is remarkable. That being so, why didn't life continue? It's very tempting to think there was an Archean biota on Mars as there was on the earth, and that a large planetesimal impact or something else tipped the balance, causing the planet to dry out subsequently and the biota to die off: Gaia has lived longer than many stars live, which is amazing considering its fragility, but one shouldn't simply assume our planet is immortal.
MOTHER: How old is the earth?
Lovelock: It's one quarter as old as the universe. To all intents and purposes, that's nearly immortal. It's incredible, really, when you think of it—though from a cosmological viewpoint, it cannot be absolutely unique. But eventually the sun's going to warm up to a point where Gaia can't survive, and maybe it's already warming to that state. I've made computer models of the weather which are zonally climate-regulated using Daisyworld-type scenarios. [Editor's Note: In Lovelock's theoretical Daisyworld, light and dark daisies regulate the environment. When the sun is weak, an outbreak of dark daisies raises the global temperature by absorbing heat. When the sun is strong, the spread of light daisies creates a reflective shield that keeps the planet cool.] They show the whole planet greening over and show it going through its evolutionary stages. In the final stage, 30° north and south of the equator, the earth becomes a desert. Then, quite suddenly—flip, like that—nothing. We're not far off that stage at the moment.
MOTHER: Are you saying that if the equatorial regions are turned into deserts, as is happening in many places today, the whole planet is at risk?
Lovelock: Don't take this too seriously. These are crude models, and I'm not putting this forward as a doom scenario, because that would be absurd. But, on the other side of the coin, you can't assume that what we're doing might not be terminally disturbing. If the scenarios are followed through to the worst point, and we don't respond, it could happen. In other words, if by the middle of the next century we let greenhouse gases build up carbon dioxide concentrations of from 600 to 1,000 parts per million, if we take away all of the forests, if we continue to do all of the bad things we're doing without letup or hindrance, then we might induce a terminal disturbance, but I don't think we will.
MOTHER: Aren't there non-human changes going on as well?
Lovelock: The sun is continuously warming up, and the planet has the problem of keeping cool. If you make models of these kinds of systems, you find that when the sun is very cool, the system tends to self-regulate on the warm side of optimum. When the sun is putting out more heat than the system can comfortably dissipate, it tends to regulate on the cold side of optimum, which is precisely what it's doing at the moment. But Gaia seems to prefer to be in a state of glaciation; there is unequivocal evidence that there was more biota present on the earth during glaciation than during the interglacial periods, one of which is now. In other words, the interglacial periods represent the fevered state of the planet. What we are doing is pushing the planet in the wrong direction when it is sick anyway.
MOTHER: You mean we're raising its temperature.
Lovelock: That's right, and just at a time when it would normally be slowly recovering to its preferred glacial state. That's why I feel a bit anxious. If we were doing this in the middle of glaciation, the worst we could do would be to precipitate an interglacial state, though that in itself would be quite dramatic, producing a 600-foot rise in sea level. What if civilization had developed during glaciation; can you imagine what a science fiction story that would make?
MOTHER: Do you think because civilized man developed during a fevered state that we are a sort of sickness, too?
Lovelock: Well, it's often the way of things. If you get sick, you're quite liable to be attacked by another sickness. That's the worrying side of it. We are doing things so contrary to what the system would want that something might well happen. For one thing, we're maniacally obsessed with human problems, like cancer.
MOTHER: In other words, there's more concern about human health than environmental health.
Lovelock: Than planetary health—because, in the end, we're much more dependent on a healthy planet than we are on healthy humans. We've got to not so much forget people problems as recognize that planetary problems are the most urgent ones that are going to confront us in the next decade or so. We've become so numerous as a species that we are having an effect on the planet that is more than can be withstood without affecting its capacity to self-regulate.
MOTHER: What will be the result?
Lovelock: The most difficult time to make predictions is in a time of transition.
If you lived in the year 1200 you could easily predict 1300, and you wouldn't be far wrong, because things were changing only slightly. But nobody can predict how it will be in 2089. I'm very uncertain what's going to happen in 10 or 20 years' time, let alone 100, because we're just entering the transition—a human-induced transition. With the best will in the world, I don't see how we're going to significantly cut back carbon dioxide and greenhouse emissions in the next 10 years. One major problem is to get people to give up driving their cars, and another is to get people in northern regions to stop heating their homes with fossil fuels. Technically, cutting back could be done, but the politics of doing it would be nearly impossible to solve. However, we might have a chance if people responded to this crisis as the Europeans did during wartime. They were prepared to make enormous sacrifices, and even felt good about doing that. The disintegration of creation is a much more serious issue, so maybe we'll meet the challenge. I'm an optimist, and I think we might. After all, peace seems to be breaking out worldwide. And we've got the resources to make the changes.
MOTHER: I'm still not sure what changes we need to make.
Lovelock: Think of the three deadly Cs: cars, cattle and chain saws. We don't have to ban them. If everybody uses them in sensible moderation, it will enormously relieve the pressures on the atmosphere and on the rain forests. It can even benefit the individual. If you use your car less, you may walk more and be healthier. If you eat less beef and dairy products, you'll improve your health and relieve pressures on the tropical forests as well. Indeed, if the world largely gave up beef, the forest-chopping-down agriculture would come to a grinding halt. These changes might give us time to get our act together; if we don't make them, the process will be remorseless, making the whole world a very nasty place to live.
MOTHER: What will happen?
Lovelock: If the present rate of clearance is sustained, the forests will all be gone by early in the next century, and roughly a billion people in the Third World will suddenly find themselves in desert regions; what has already happened in south Sudan is going to be global, involving not just a few million but a billion people. The awful consequences of this from the human point of view don't seem to be appreciated at all. There also will be secondary climatic consequences: The heat-up of all those regions, once the forests are gone, will add to the greenhouse effect and may be an additional factor precipitating a final flip to something else.
In fact, I classify the clearance of the tropical forests as by far the most important issue at the moment, mainly because its effect is certain. The second issue is greenhouse gases, and among them, methane is by far the most important. Though hardly anybody mentions methane, there are three reasons for concern. First, the Third World's rice paddies and the deforestation for the purpose of raising cattle both add to the methane output. Second, methane, unlike all other greenhouse gases, is nonlinear in the wrong direction. That is to say, each increment of methane has a larger effect than the one before, while carbon dioxide is the other way around. Third, not only do fluorocarbons create ozone depletion, but methane does too, and that's the one we can do the least about.
These are fairly straightforward messages. But I think there will be a reinforcing one: In the beginning of the transition, especially if the cloud-algal effect is valid, we will get enormous surprises. As the global systems try to sustain the environment by cooling—possibly with the cloud-algal response to the greenhouse warming—they will create a sort of battlefield. Instead of a steady heating up, we may have violent storms, the like of which we've never seen before. I've a feeling that the storm that crossed Britain in 1987 and last year's Hurricane Gilbert are two examples of the climatic disturbances that will become commonplace. If Gilbert had hit Florida straight on from the sea, I think that people would have gotten the message about coming global changes and the need to take action. The damage caused by winds at 200 mph is four times that at 100 mph.
MOTHER: As the Gaian systems respond to the damage human beings are inflicting on them—as mother earth symbolically takes her "revenge" for our excesses—perhaps the Gaia hypothesis itself will then be more accepted by mainstream science.
Lovelock: I think the Gaia hypothesis could be very ecumenical in a broad sense. I've noticed that whenever there are major meetings on Gaia, scientists who normally would never talk to one another either because their disciplines are totally different or because of hostilities—are conversing in an amazingly docile and friendly manner. A totally holistic approach seems to make sectarian differences less important. It's "detribalizing," and that's good, because I see a wartime-equivalent situation upon us, which means we've got to give up a lot of luxury thinking. We've got to take risks and do things we wouldn't ordinarily do in peacetime.
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