2 February 2007
Planetary Maintenance Engineer
By Gwynne Dyer
Twenty-eight years ago, when we knew very little about the way human activities affect global climate, independent scientist James Lovelock warned that the sheer scale of human activities threatened to destabilise the homoeostatic system that keeps the Earth’s climate within a comfortable range for our kind of life, the system he named “Gaia.” “We shall have to tread carefully,” he said, “to avoid the cybernetic disasters of runaway positive feedback or sustained oscillation.”
Then he said something that has stuck in my mind ever since. If we overwhelm the natural systems that keep the climate stable, Lovelock predicted, then we would “wake up one morning to find that [we] had the permanent lifelong job of planetary maintenance engineer….The ceaseless intricate task of keeping all the global cycles in balance would be ours. Then at last we should be riding that strange contraption, the ‘spaceship Earth’, and whatever tamed and domesticated biosphere remained would indeed be our ‘life support system’.”
I have a nasty feeling that we are almost there. The years have passed, our numbers and our emissions have grown — have almost doubled since 1979, in fact — and the crisis is now upon us. The fourth assessment of the Intergovernmental Panel on Climate Change, published on Friday, says that global temperature rises of between 2 degrees and 4.5 degrees Celsius (3.6 and 8.1 degrees Fahrenheit) are almost inevitable in the course of this century — but much higher increases of 6 degrees C (10.8 F) or even more cannot be ruled out.
The IPCC reports are produced by some 2,000 of the world’s leading climate scientists, nominated by their various national governments, and they operate by consensus, so any predictions they make are likely to err on the conservative side. And they say the argument is over: “It is highly likely [greater than 95 percent probability] that the warming observed during the past half century cannot be explained without external forcing [i.e. human activity].” Indeed, the sum of solar and volcanic influences on the system ought to be producing global cooling right now, if it were not for the human factor.
It’s already worse than you think, the IPCC reports, because the sulphate particles that pollute the upper atmosphere as a result of human industrial activity are acting as a kind of sunscreen: without them, the average global temperature would already be 0.8 degrees C (1.2 degrees F) higher. And the report goes on to talk about killer heat waves, more and bigger tropical storms, melting glaciers and rising sea levels — but it doesn’t really get into the worst implication of major global heating: mass starvation.
If the global average temperature rises by 4.5 degrees C (8.1 degrees F), shifting rainfall patterns will bring perpetual drought to most of the world’s major breadbaskets (the north Indian plain, the Chinese river valleys, the US Midwest, the Nile watershed), and reduce global food production by 25 to 50 percent. If it goes to 6 degrees C (10.8 degrees F), we lose most of our food production worldwide.
The world’s six and a half billion people currently produce just about enough food to keep everybody alive (although it is so unevenly shared out that some of us don’t stay alive). Any major reduction in food production means mass migrations, war, and mass death. It is getting very serious.
Obviously, the main part of the solution must be to reduce our greenhouse gas emissions and stop destabilising the climate, but we are probably not going to be able to get them down far enough, fast enough, to avoid catastrophe. Short-term technological fixes to keep the worst from happening while we work at getting emissions down would be very welcome, and a variety are now on offer. But they are all controversial.
Bring back nuclear power generation on a huge scale, and stop generating electricity by burning fossil fuels. Fill the upper atmosphere with even more sulphate particles (you could just dose jet fuel with one-half percent sulphur) to thicken the sunscreen effect. Scrub carbon out of the air by windmill-like machines that capture and sequester it. Seed clouds over the ocean with atomised sea-water to make them whiter and more reflective. Float a fleet of tiny aluminium balloons in the upper atmosphere to reflect sunlight or orbit a giant mirror in space between the Earth and the Sun to do the same job.
The purists hate it, and insist that we can do it all by conserving energy and shifting to non-carbon energy sources. In the long run, of course, they are right, but we must survive the short run if we ever hope to see the long run, and that may well require short-term techno-fixes. Welcome to the job of planetary maintenance engineer.
We won’t like the job a bit, but Lovelock stated our remaining options eloquently twenty-eight years ago. If the consumption of energy continues to increase, he wrote, we face “the final choice of permanent enslavement on the prison hulk of spaceship Earth, or gigadeath to enable the survivors to restore a Gaian world.”
Maybe in a couple of centuries the human race will be able to restore the natural cycles and give up the job again, but it won’t happen in our lifetimes, or our children’s either.
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To shorten to 725 words, omit paragraphs 4 and 7. (“The IPCC…factor”;and “The world’s…serious”)
NOTE TO TRANSLATORS: Don’t bother converting the temperatures into Fahrenheit.