Homage to Gaia

by James Lovelock

  When I analysed the clean air samples they showed the expected northern hemispheric background level of CFCs, about sixty parts per trillion: this was no smoggy air mass. I began to collect PAN samples throughout the day and soon found that the level varied with the position of the sun. There was little at dawn or dusk and the maximum in the early afternoon. So the photochemistry that made it must be local; the sea must be emitting hydrocarbons and nitrogen compounds. Rasmussen confirmed that the sea was a source of hydrocarbons and I now know from the work of my friend, Peter Liss, that it is also a source of amines. These nitrogen compounds would oxidize in the atmosphere to give the nitrogen dioxide from which PAN can form.

  We were now well into the Sargasso Sea; everywhere were fronds of seaweed, Fucus-like, with bladders to keep them afloat. They were not dense and entangling but sprinkled over the waters of a clear blue sea. Nature has a way of leading scientists up the garden path and then suddenly removing the garden. For reasons I now forget, I sampled the air the next day with a polypropylene syringe, instead of the glass ones I usually used. To my dismay, the PAN had vanished. I tried again with the glass syringe, and there it was back again. Was the polypropylene surface destroying PAN? Unlikely, I thought. I would have expected the reverse, for PAN decomposes on glass surfaces but is stable towards polypropylene. I then tried incorporating a piece of glass wool into the polypropylene syringe and the PAN came back again in full quantity. It looked as if what I had thought was PAN in the air was in fact PAN coming from the reaction of something in the air with a glass surface. This was even more mysterious. What could be in the air out over the ocean that reacted so rapidly on the surface to make PAN? I could only guess that it was a mixture of nitrogen dioxide and a free radical precursor such as the acetyl peroxy radical. I knew that the methyl peroxy radical was a common product of methane oxidation, which goes on everywhere. Was the product of its reaction with nitrogen oxide also present? There was certainly always a peak well before PAN which, like PAN, was present only when the sun shone. Having no means of proving it or its precursor’s presence, I can only guess that methyl peroxy nitrate was also there, forming on surfaces in this clear remote place. This odd phenomenon kept me occupied until we reached our destination, Santo Domingo. The results of these preliminary investigations appeared in a Nature Letter, called ‘PAN over the Atlantic and the smell of clean linen’ in 1974.

  I had many lively discussions with the German students working on the Meteor. One that recurred was about the Nazi period and the Holocaust. These young men felt strongly that it was inappropriate and unjust for the world continuously to remind them of the wrongs done in the Second World War. It was not that they wanted to bury the history or pretend that there was no evil. It was that they felt the injustice of being held personally responsible for deeds done before they were born. I strongly sympathized, and remembered my own angst when spiteful Irish republicans visited me with their synthetic tribal rage over the Irish famine those years long ago. We wondered if any nation is so free of the taint of genocide that it can cast a stone. We wondered, too, if the constant reminders of past atrocities are themselves driven by racial hatred.

  Ten days after we entered the Sargasso Sea, there was a strange encounter with another ship, the USSR intelligence-gathering vessel, the Gregyor Ushikov. It seemed large compared with the Meteor, and kept station with us about a few hundred yards away. Antennae of all kinds festooned it, and we discovered through an exchange of visits that it had drifted along the whole length of the American coastline from Canada. The crew had been at sea for months since leaving their Black Sea port and were glad to exchange visits with us on the Meteor. Their hospitality was vigorous, and the Germans who went to the Russian ship had difficulty staying sober. There were no convenient flowerpots in which to pour the vodka that was plied to them. I had a nagging feeling that it would be unwise for me, in those Cold War times, to visit the Gregyor Ushikov. I was well aware of the many secrets in my mind that I might inadvertently reveal in the vodka-rich environment. So I kept a low profile and stayed on the Meteor, using work as an excuse. Now that the Cold War is long past, I doubt I would have been at risk on the Russian ship, but those were difficult times.

  Soon we were at our destination, Santo Domingo. The Meteor was due to leave in three days, so on the first day I stayed aboard, using it as a floating hotel. And the last day before flying home, I planned to stay at a seashore hotel in Santo Domingo. With Rai Rasmussen and a few German friends, we left the ship the next morning for a walk into town. As we descended the gangway a group of young black boys, aged between about eight and fourteen, came to us and offered to show us the town. They were friendly and seemed so innocent in the way they took us by the hand that we all went with them. Our first port of call was a bank to change our money into local currency. In those days the British Pound was a weak coinage based on an always-unstable economy, and my companions expected that the bank would accept only Marks and Dollars. To my astonishment and delight, in fact, only Pounds and Dollars were acceptable. Marks were not wanted. The Caribbean, it seemed, operated as if it were still in a British sphere of influence. I doubt if this is still true twenty-five years on. We bought a few trinkets and postcards, had some coffee with the boys at a café, and then returned to the ship for lunch. We rewarded the boys for their guidance and they were quietly grateful. Their dignity was impressive.

  When I returned to my cabin on the ship, a letter waiting on my desk surprised me. It was an invitation to dinner that evening at the German Embassy where the guest of honour would be the President of the Santo Domingo Republic. Panic-struck, I was still young enough to care that I had not even a work suit with me, just a blazer, a clean pair of trousers, some bright red socks, and some comfortable casual shoes. The car to take us to the Embassy arrived at seven. The other guest was to be the German Chief Scientist. To add to my feelings of inferiority, induced by my odd attire, they all wore good quality dark suits and everyone spoke perfect English; not just grammatically perfect, but that kind of English that reveals instantly an education at a good public school. My discomfort soon vanished in the euphoria of the good wine served with the meal, and in the warmth of interest shown by the President and his Chief of Staff in marine biology. They seemed to be scientists and were keen to build an institute like the Marine Biology Laboratory at Plymouth. They wanted to build it on the seacoast not far from Santo Domingo. The only jarring moment of the evening was before dinner when I crossed my legs and revealed the vivid scarlet socks I wore. ‘My God,’ said a German diplomat, ‘red socks.’ He added, ‘My mother told me never to trust a man who wore red socks.’ Everyone laughed. I just wore a sickly grin that clashed with the socks. However, the moment soon passed, and it was a very pleasant evening.

  The next day I saw another side of Santo Domingo. The Ambassador had recommended a hotel a short distance along the coast, and I intended to spend my last night there with my German scientist companions. In the morning, we hired a taxi and told the driver where we wanted to go. Halfway there the taxi broke down and the driver explained that he would have to walk back to the city to get spare parts. ‘However,’ he smiled and said, ‘you could, of course, stay at the hotel just here, just down that road there. It’s just as good as the one you were going to.’ From the outside, it looked good—a modern building in a scenic setting by the sea. Therefore, we chose to stay, not realizing that the driver had probably dropped us there deliberately. We went in, registered, and were shown to our rooms. The Germans discovered long before I did that it was not merely a hotel, but also a brothel. We sat at the tables outside by the sea and had soft drinks in the shade of palms. Young girls, perhaps the sisters of the boys who met us the previous day at the ship, came and joined us at the table. The notion of casual sex with a prostitute has never appealed to me, no matter how attractive the girl might be. To be turned on to a strong desire requires for me a loving relationship. Also, there was the high probability of infection with one of th
e many organisms that opportunistically use the tight coupling of sex as part of their life cycle. I returned to my room, collected my swimsuit and towel, and went down to the sea to bathe. Here I had another shock. I went to put my towel on the beach and nearly put it on a wasp’s nest. To my dismay, there were nests at frequent intervals along the sandy beach. I have a fear of wasps which is very strong, and the thought of stumbling, shortsighted and naked but for swimming trunks, onto a nest quite spoilt the thought of bathing. I chose a spot near the sea, dashed into the shallow warm water, and tried to swim. It was not at all like the visions I had had of a tropical island. I seemed to have to walk forever to get any depth of water. Soon I was back in my room at the hotel and reading a novel. When darkness came at 6 pm, I discovered there was no electric light at this brothel that pretended to be a hotel. I suppose the normal customers did not need it. Worse, there was no water. When I complained they gave me a jug of water and a candle. It was a miserable night; too hot to sleep with the windows closed, and too many mosquitoes with them open, and I longed for dawn. When it came, I dressed, packed, and went downstairs. There was no breakfast, only coffee. I took the first available taxi to the airport, anxious that it would get there and not to some unscheduled tourist trap, with which the cab driver had a private contract.

  We arrived at the airport and I checked in at the airline desk. The plane left on time and after a short flight, stopped at Port au Prince in Haiti, which, of course, is a country sharing the same island as Santo Domingo. This was the closest I would be to the notorious Papa Doc, his family, and the Ton Ton Macoute. I was thankful when we took off for Miami, where there would be the British Airways connection to London and home. I often try to fly the airline of the nation to which it is flying. The pilot and crew have a personal stake in getting there, so it is less likely to over-fly to some unwanted city.

  9

  The Quest for Gaia

  An eminent scientist recently spoke of me as ‘a holy fool’. He may of course have meant ‘wholly’, but I like to think he saw me spending my life in a quest for Gaia as if it were the Holy Grail. In recent years I have grown fond of Wagner’s operas, especially Parsifal, so that whatever was meant by it, to be called a holy fool is for me an accolade. Can there have been any more inspiring vision this century than that of the Earth from space? We saw for the first time what a gem of a planet we live on. The astronauts who saw the whole Earth from Apollo 8 gave us an icon that has become as powerful as the scimitar or the cross. In the years leading up to this mission in 1968, I had worked with the American National Aeronautical and Space Administration (NASA) and had seen behind the scenes. The meaning of that cloud-speckled ocean-blue sphere was made real to me by their newly won scientific information about the Earth and its sibling planets Mars and Venus. Suddenly, as a revelation, I saw the Earth as a living planet. The quest to know and understand our planet as one that behaves like something alive, and which has kept a home for us, has been the Grail that beckoned me ever since. Moments of intuition do not come from an empty mind; they require the gathering together of many apparently unconnected facts. The intuition that the Earth controls its surface and atmosphere to keep the environment always benign for life came to me one afternoon in September 1965 at the Jet Propulsion Laboratory (JPL) in California and it was here that most of these facts were gathered. Let me tell you more about those early days in California and how they led me to the Gaia theory.

  I first visited JPL in April 1961, and in those days it had the hasty air of a temporary airport, with prefabricated cabins dotted over the hillside above the dry river bed of Arroyo Seco. I was sitting at a table in one of these cabins with about a dozen scientists and engineers. We might have been discussing the design of a new hospital or a farm tractor, but in fact we were talking about the surface of the Moon and what the proposed lander, the Surveyor, might find there. We talked in the most matter-of-fact way about how to collect samples of the lunar surface. I learnt that they needed me for my expertise as an inventor of exceedingly sensitive devices that they could use aboard their spacecraft. Every few minutes I had to pinch myself to make sure I was there with these other ordinary humans discussing such an extraordinary project. Even a few years previously, it would have been inconceivable. I made many more visits to JPL during the next twelve years up to just before the Viking spacecraft went to Mars in 1975. These visits were rarely more than three weeks long, and I usually stayed at the Huntington Sheraton Hotel in Pasadena. It was a rather unusual hotel for America. A grand brick-built building, almost like a stately home, standing in its own extensive beautifully landscaped grounds. It was unusual to have a brick-built building in an earthquake-prone area like Los Angeles, but there it was and it seemed to have stood up to the lesser shocks quite as well as anything else around. It had a comfortable old-fashioned air to it; such a change from cold unfeeling modern hotels with their clinical reception areas—no chairs to sit on and just a battery of lifts to take the guests to their various rooms. At the Huntington Sheraton, there were porters, a huge lounge, and quite a few old people sitting around. It seemed more like Bournemouth than Pasadena.

  On one visit, a kindly giant of a man, George Hobby, came to take me to the JPL, and when they said that he understudied Tarzan at the nearby Hollywood studios, I could well believe it. We travelled the short distance to the laboratory in his small European sports car. George, a biologist, wanted me to sit in on a meeting of potential experimenters for the mission to Mars to find life there. He and others had the view that space biology was perhaps losing its way, getting out of hand. He was right, for as I listened to the experimenters describing the equipment they would use to find Martian life I doubted their capability. There was, for example, the Wolf trap. Not, I might add, a device to catch wolves, but a device named after its inventor, Wolf Visniak, and designed to collect and grow micro-organisms from the Martian soil. A chemist, Vance Oyama wanted to collect soil from the Mars surface and analyse it for what he and others called life-characteristic substances. The flaw in their thinking was their assumption that they already knew what Martian life was like. From them, I gathered the distinct impression that they saw it as like life in the Mojave Desert, to the east of Los Angeles. This was convenient, for the Mojave Desert was close by and the experimenters could go there to test their equipment. Perhaps Mars was like this, but no one seemed to ask, what if it is different? Will its organisms grow on our culture media? What happens if the spacecraft lands at a barren place? Even on the Earth, a spacecraft might land on polar ice or on a sand dune in the desert.

  Towards the end of the day I said, ‘I think we need a general experiment, something that could look for life itself, not the familiar attributes of life that we have here on Earth.’ This seemed to annoy many of those present, and my comment must have been repeated to one of the more senior laboratory chiefs. The next day Dr Meghreblian, a tough character held somewhat in awe by the staff there, asked me to come to his office. He asked, courteously, what I thought of the biological experiments. I replied that I did not think they justified the cost of sending them to Mars. His next question was the obvious one. ‘Well, what would you send instead?’ With some hesitation I said, ‘I would send an experiment that looked for an entropy reduction.’ He smiled, knowing that entropy is one of the most confusing topics and the bane of students, and said, ‘That would be fine, but how could you do it?’ At this point, I was not ready to reply and asked for a day or two to think about it. ‘Okay,’ said he, ‘Come back on Friday afternoon and tell me how we’re going to send an entropy reduction experiment to Mars.’ Challenges like this have that quality observed by Dr Johnson in his famous remark, ‘There’s nothing like the prospect of hanging to concentrate the mind.’ And so it was with me. Forced to think of ways to measure entropy reduction led me to read Schrödinger’s famous little book, What is Life? I owe a great deal to Schrödinger and that book: it set me on the right track. I was mainly concerned to find out if the entropy reductio
n characteristic of life was easily distinguishable from the small entropy reduction of a lifeless planet illuminated by the Sun. Anyone who wants to know what entropy is could not do better than read the Oxford physical chemist, Professor PW Atkins’s splendid book, The Second Law. Entropy, like temperature, can be measured precisely, and it indicates the degree of disorganization of a system.

  This book confirmed my intuitive feeling that we could recognize life elsewhere by the signature of its low entropy. I returned on Friday to Meghreblian’s office and gave him a set of experiments that would use entropy reduction as an indicator of planetary life. The first and best of these was simply to analyse the chemical composition of the Martian atmosphere. The argument behind it was quite simple. If there were no life on Mars, the atmosphere would be close to the chemical equilibrium state, which is one of high entropy. If there were life on Mars, it would be obliged to use the atmosphere as a source of its raw materials and a place to deposit its waste products, just as we do. When I say waste products here I am not thinking of junk or pollution, I am thinking of the carbon dioxide we exhale which is to us a waste product. Plants breathe out oxygen, which is to them a waste product and the exchange between producers and consumers is what keeps life going. I knew that these processes would change the composition of a planet’s atmosphere, whether it’s Mars or the Earth, in such a way as to lower its entropy. This would make it recognizably different chemically from the atmosphere of a dead high-entropy planet. This was my fundamental life-detection experiment.