Homage to Gaia

by James Lovelock

  The National Bureau of Standards report in 1978 renewed my trust in absolute detection. I decided to validate it as a method. This I did by building a fifty-cubic-metre chamber, hermetically sealed, within an old barn deep in the Devon countryside. The idea I had was to prepare accurately small volumes of chlorofluorocarbon gas by a vacuum line procedure. Graham Milne, an ICI scientist, gave me the apparatus needed for this and generously gave his time teaching me how to use it. First, I prepared an accurately known volume of chlorofluorocarbon gas in a sealed glass ampoule and then took the ampoule to the barn and placed it before a powerful fan. I then left the chamber and set my instruments running, taking samples of the background air of the chamber, and then I broke the ampoule by an electrically driven crusher. The chamber air was continuously refreshed by air from outside at a rate of two air changes an hour. At intervals, samples of the chamber air were taken and measured. I checked the accuracy of this dilution method by also releasing hydrogen gas into the chamber, and following its dilution using a well-calibrated thermal-conductivity detector. Whilst I was doing these experiments, a family of barn owls took residence in the space above the chamber. The barn programme kept me busy for nearly three years, and it was some of the most exacting and least rewarding financially of my life’s work as a scientist. It was worthwhile because it did make honest the atmospheric CFC measurements, and it did confirm that the ECD could be an absolute detector for the chlorofluorocarbons. Most of all, for me, it justified my estimate of the accuracy of the Shackleton data. The paper describing these experiments in the barn appeared in Geophysical Reviews in 1984. For reasons I never understood, the ALE management team insisted that it appear as a joint paper with Rai Rasmussen, a member of the ALE team, as the lead author. Nevertheless, I did the barn experiments unaided by anyone.

  During the time of the barn experiments my friend, Brian Foulger, and I made a series of measurements of the atmospheric abundance of halons, the bromine-rich compounds used as fire extinguishers. We made them here at Coombe Mill and in the southern hemisphere at Cape Town and in New Zealand. We found about 1.5 parts per trillion in the northern hemisphere and 0.6 in the southern hemisphere. The chemical company, ICI, funded the work. Unusually, but as was their right, they persistently refused us permission to publish these findings. This was the only time in my life as an independent scientist that a company or a government department blocked the publication of important scientific information.

  The Ozone War was curiously involved with low-budget science done by British scientists in or near Antarctica. The voyage of the Shackleton to Antarctica in 1971 first drew attention to the global distribution of CFCs. The discovery by Joe Farman and Brian Gardiner of the thinning of ozone above the Antarctic landmass made us realize how serious it was. These were quiet, inexpensive researches inspired by a sense of wonder, and we were all inspired by the theory of Molina and Rowland in California, which was a modestly funded research. We need big science to complete our understanding of the intricate chemistry of the stratosphere, but we must never forget that pioneering small-scale research is just as necessary. I started the CFC ozone affair as small science, but by 1982 it seemed that I was on an accelerating bandwagon, and now was the time to jump off. At the end of that year, I fell ill and was unable to travel. I was glad that illness gave me the chance to escape what was now big science. I have never returned to it.

  The Voyage of the Meteor in 1973

  On the voyage of the Shackleton I had as a companion in the next laboratory on the ship a striking and friendly young German student, Hans Greese. His task on the voyage was the difficult one of measuring atmospheric carbon monoxide. Like me, he wanted to know how it varied between the northern and southern hemispheres. My equipment was simple, home-made and occupied no more than four square feet of bench space. His was intricate and filled the whole of the front laboratory of the ship. I was fortunate to have the electron capture detector, which is specifically sensitive to the chlorofluorocarbons that I sought. Hans had to do it the hard way by extracting the tiny proportion of carbon monoxide, less than a part per million, from the air by standard chemical methods, and then measuring it by chemical quantitative analysis. Just as I was impressed with his professionalism and craftsmanship, he was impressed with the simplicity and sensitivity of my chlorofluorocarbon measurements. In some ways, it typified the different approaches of our two nations: the German as painstaking and professional and the English as opportunistic but effective amateurs. He must have talked with his colleagues and his supervisor, Dr Wolfgang Seiler, when he returned to Germany. The distinguished scientist, Christian Jünge, was director of the Max Planck Institute of Atmospheric Science at Mainz in Germany. He wrote to me inviting me to Mainz to tell them of the discoveries made during my voyage on the Shackleton.

  I travelled to Mainz sometime in the autumn of 1972. Dr JH Hahn met me at Frankfurt Airport and drove me by car to Mainz. They let me stay in the Institute guesthouse and Dr Hahn arranged to meet me there at 9 o’clock the next morning. After a good night’s sleep, I awoke hungry and ready for breakfast, and then a good day of talks about the atmosphere. I wandered around the guesthouse but seemed to be the only one there. There was no dining room and I could not smell coffee brewing or breakfast cooking. Hahn appeared sharp at 9 and I asked, ‘Are we going to have breakfast?’ ‘Breakfast?,’ he said with a grin, ‘you must have a German breakfast: a cup of coffee at the lab and a cigarette.’ This was a culture shock for me. Breakfast is the most important meal of the day for the English. I don’t go in for the whole thing: grapefruit and porridge, followed by egg, bacon, fried potatoes, tomatoes, and finished off by rounds of buttered toast and marmalade, all washed down with a large quantity of good strong tea. But to start the day on an empty stomach and no cup of tea was too much. I asked if there was a shop that sold something light. Jürgen Hahn kindly, sensing my lack of food, took me to a café where there were cakes and beer available. I settled for the cake and then returned with him to the Institute, where there was coffee brewing all of the time.

  I was much impressed with the atmosphere and quality of the scientists there. Christian Jünge reminded me of Sir Charles Harington. He was a quiet, strong, and authoritative man with a towering intellect. We had a happy morning discussing the significance of the Shackleton analyses. Jünge had proposed in an earlier paper a way to estimate the atmospheric lifetime of a gas. He guessed that long-lived gases such as oxygen and nitrogen would not vary in abundance by a detectable amount, whereas short-lived gases like methane or carbon monoxide, with residence times of a few years or months, would fluctuate considerably in abundance. This approach suggested that the chlorofluorocarbons, in the southern hemisphere at least, had a long lifetime, which later we found to be over a hundred years.

  Almost all of the Germans I met spoke good English and I felt ashamed at my lack of language. It was a pleasant stay and towards the end, Christian Jünge invited me to make another sea voyage, this time on the German research ship, Meteor. It was due to sail from Hamburg to Santo Domingo in the Caribbean in late 1973. What a wonderful ending for my visit: the prospect of another sea voyage filled me with joy and I now had something to look forward to and prepare for during the next year.

  I flew to Hamburg in 1973 and a scientist from the ship met me, and took me to a pension near the port where many of the ship’s company were staying. I was deeply aware that in the Second World War Hamburg had suffered the greatest civilian casualties of any bombing raid during the whole of that war, even more than were caused by the atom bombs in Japan. Close to 250,000 died in one night of intensive bombing, far beyond anything we had suffered in London. I was amazed at the extent to which they had rebuilt the city. No scars were visible to me in my journeys across it, nor did I detect any personal animosity towards me as a representative of the tribe that had so barbarously executed the terror bombing.

  The next day, after breakfast, we climbed into a station wagon with our suitcases full of person
al belongings and clothes to wear on the voyage. I had some spare old clothes, one good jacket in case of need, and some books to read. The journey to the dock was short, and soon we were wending our way past port cranes hunched mournfully against the morning sky, and past warehouses full of boxes and men with forklift trucks. Of all the working scenes, none has quite the capacity to move me like that of a dock area. The foreplay of preparation for a sea voyage has an excitement more than that of any other journey. Air travel is a dull thing by comparison; mostly a set of encounters with officials and bureaucrats in a peculiar kind of air-conditioned office called an airport. If all one’s papers satisfy them they dispatch you down a pipe like one of those pneumatic account carriers that added mystery to the old-fashioned department store.

  We left the car and looked at the sizeable bulk of the Meteor, not at all like the tiny Shackleton. Here was a shipshape floating palace full of laboratories. One of the ship’s officers took me up the gangway and to a spacious top deck cabin, and here I met Dr Rai Rasmussen, an American scientist who was to share the cabin with me for the voyage. I was somewhat dismayed to be sharing a cabin. I am a private person and do not like sharing living quarters with strangers, but there was little I could do about it. As it happened, I soon found that Rai Rasmussen was a quiet and courteous person at close quarters. We soon, as the only two foreigners aboard the ship, were driven together and spent the voyage amicably. After settling in I went down to the lab assigned to me where I found the box with all of my equipment waiting. I spent the rest of the morning connecting it up, and by lunchtime my gas Chromatograph was running. There was a spacious bench for me, and an excellent drawer and cupboard space below it. A friendly German graduate student who, like so many Germans, spoke English better than many of my countrymen, occupied the other half of the lab.

  There was a spacious and well-equipped dining room on the Meteor and I looked forward to an encounter here with the German scientists who were to travel with me down the Atlantic to Santo Domingo. I had hoped to improve my German during the voyage to the point of colloquial conversation. It was not to be. Not even the sailors on deck would speak to me in anything but English. They always replied to my halting German phrases with a rejoinder in near perfect English, not rudely, but because life was too short to waste time over a mismatch in language. Lunch, indeed all lunches on the Meteor, were substantial German meals. To my taste, they were disappointing and too rich, but they were more than adequate for health. I missed the near gourmet food of the Shackleton and of the Navy ships. Breakfast, thankfully, was no continental breakfast of coffee and rolls. There was more, and it was adequate. The other meal, high tea at 5 o’clock, was the hardest to cope with: just quantities of bread and butter and a variety of cold sausages. I longed for some fresh fruit and vegetables, but there were none. Food is very much a cultural affair, and no doubt Hans, my companion on the Shackleton, would have found something to complain about with our food. There was a shop on the ship where Rasmussen and I bought chocolate to satisfy our craving for something sweet.

  We set sail soon after we had boarded the ship, and in the afternoon I saw something of the flat landscape that bordered the Elbe estuary. It was a clear day and a wide sky, so beloved of Flemish painters, illuminated the smooth movement of the ship. The open decks were spacious and there was plenty of room to walk and to explore. In the evening I made the first chlorofluorocarbon measurements and found them to be well over 300 parts per trillion. This was unbelievable, for we were already out in the North Sea and the wind was off the sea, not the land. I soon discovered that the CFC level in the ship itself was so high, approaching one part per million, that measurement of CFCs in the lab on the Meteor was all but impossible with the equipment I had brought with me. The heavy halocarbon contamination came from several sources: some meteorologists aboard the ship had filled Dewar flasks with chlorofluorocarbons, from which CFCs vented to the ship’s air. Other scientists were using carbon tetrachloride as a solvent for Vaseline, which they coated on glass slides. The sticky slides were then used to collect aerosol particles in the air the ship passed through. Most of the ship’s company also used aerosol sprays powered by chlorofluorocarbons as deodorants and for shaving soap. The tightly closed and air-conditioned quarters of the ship kept the air inside and these rich sources caused the Meteor to have the highest concentration of halocarbons in any air I have ever measured. It was not the place to monitor atmospheric CFCs.

  I had looked forward to seeing the Straits of Dover as we passed through that narrow part of the Channel, but it was dark and all that I could see were faint lights on shore. The ship moved comfortably in the Atlantic swell that came up the Channel. It was a more stable platform to work on than the Shackleton had been. I noticed no one seasick, even on the first day, and the whole voyage seemed to be one of unusually calm weather. Rai Rasmussen was busy measuring hydrocarbons in the air and in the water. He used a far more expensive and complicated commercial gas Chromatograph. He was curious about my simple gas Chromatograph and astonished to find it over a thousand times more sensitive than the equipment that he was using. It may have been his first encounter with electron capture gas chromatography. The ECD was so sensitive, so unpredictable, and so little understood that analysts regarded it with suspicion.

  Science to me has always been something to wonder about and to have the daily ration of curiosity satisfied by successful experiments: to speculate then experiment, measure, or calculate. To my travel companion, science was a battleground, with castle walls to be breached or clambered over. He looked like his name, Rasmussen, a Viking. He had the Viking’s untamed ambition and desire to win whatever the cost. When I said I would abandon my chlorofluorocarbon study because of the ship’s excessive contamination, his response was to urge me to demand immediately the banning of aerosols by the crew and scientists aboard. Fortunately for both of us, I knew how easy it is to upset a ship’s company. It would not be a good idea to interfere with the daily routine of life unless the cause was truly serious; moreover, we were guests on a German ship. When I said, ‘No, I’m going to find some other project to occupy me on this voyage and forget the CFCs’, I think Rai Rasmussen regarded me as a wimp, albeit a talented one.

  What makes me an unusual scientist is a capacious and immediately accessible memory. Anything I read, or hear, or see that interests me stays with me and is available. I have never used card indexes or computer databanks. I try to keep it all in my head. It says something of the deficiencies of my character that this memory is not available for people’s names, which I forget within seconds of hearing them. My memory, and some forethought during packing at Bowerchalke before the voyage, gave me a second project. I had included in the box sent to the ship several gas Chromatograph columns that were suited to the analysis of other compounds than the chlorofluorocarbons. I did this because I expected to find on the voyage some other interesting substances in the air or the sea. The speed with which substances pass through a gas Chromatograph column and appear at the detector is characteristic of their nature and can help to identify them. With several different columns, each of which has a different speed of passage for any given substance, the identification becomes more certain.

  I noticed that after standing on the deck my skin and my shirt had a strong chlorine-like odour and I remembered that the notorious air pollutant called PAN smelt like chlorine. This is a peculiar substance, discovered as a major component of Los Angeles smog by the American scientist, ER Stephens in 1956. The pure substance is so dangerous that experimenters usually handle it as a dilute concentration in air or some inert gas. Pure PAN explodes violently at any number of pretexts, which include contact with rough surfaces, exposure to bright lights or sudden warmth. Therefore, we avoid ever using it. For those interested, the letters PAN are the initials of the word peroxy-acetyl-nitrate.

  It so happened that I had brought with me a column just right for the analysis of PAN. It was filled with a powder coated with polyethylene gl
ycol. I joined it up in place of the CFC column of my gas Chromatograph, went on deck, and collected a few air samples. Sure enough, when I applied them to the Chromatograph a peak appeared on the recorder at the time that I expected PAN to appear from the column. There were also three other peaks whose identity I did not know. I tried the same measurement a few more times and with the same result. I speculated that if this were PAN then it was in an air mass that had drifted from Europe into the air above the Atlantic. Here was a simple project for me. I could take daily measurements and follow the ship’s passage through and out of the polluted air mass. I wished that I could have measured chlorofluorocarbons as well, to confirm the urban origins of the PAN, but it was not to be.

  As the days went by, we moved west and south, ever further out into the Atlantic. To my surprise, the PAN in the air increased rather than decreased and was present even when the air was obviously clear, sparkling, and free of smog. My guess that it came from some distant pollution source looked to be wrong. Where could it have come from, so far out over the ocean? As we sailed further south, the sunlight increased, and it became warm enough on deck for open shirts and shorts. The PAN increased still more in abundance, although we were further than ever from land. It could not have come from a maritime industrial source, such as a fleet of fishing vessels and factory ships, for we were now in the notorious Bermuda Triangle, where few ships ever go. I asked permission to go out far away from the Meteor in a rubber boat and collect just a few CFC samples to confirm that we were truly away from urban industrial air masses. Permission was given and a German sailor took me in a zodiac-type craft about a mile away from the ship, which was at the time stationary. It was quite eerie to be in this boat and look back across a mile of empty ocean towards the small image of the Meteor waiting there. I felt as the astronauts must have done on seeing the Earth from the Moon, so small it was and so far away. I hastily gathered my clean air samples and the German sailor grinned and pointed to the Meteor. He was glad, like me, to be returning to our home.