The Independent - Questions from readers - answered by James Lovelock

James Lovelock: You Ask The Questions

The eminent scientist answers your questions, such as 'Is the Earth really aliving organism?' and 'Why do you like nuclear power?'

Monday, 9 March 2009

Carbon cuts 'only give 50/50 chance of saving planet' I have heard that the Gaia theory means that the Earth is alive. What doesthat mean, exactly? Roger Middleton, Chester

The Earth system (Gaia) shares many attributes with a living cell; itmetabolises, it responds to changes in its environment, it can die, and itreduces its internal entropy by taking in high quantum energy as sunlightand excreting infra-red radiation to space. It does not reproduce, butsomething that has lived about 3 billion years hardly needs to reproduce;selection theory asserts that organisms reproduce at a rate reciprocallyrelated to their lifespan. Gaia's reproduction rate would therefore beexpected to be less than one in three billion years.

Some scientists say that your suggestions for geoengineering sea algae willnever work. Is it just pie in the sky? Guy Brewer, Nottingham

Those who claim that encouraging algal growth in the ocean will not reduceCO2 abundance in the air might be right, but they do not know for sure.Their arguments are based on calculations using theoretical models and not,as they should be in science, on observation and experiment. Evidence fromthe ice cores of Antarctica and from ocean sediments suggests that algalgrowth was more abundant in the ice ages. We also know from Antarctic icecore data that the low temperatures of the ice age were closely associatedwith low CO2. It reached as low as 180 parts per million, and this requirespowerful biological pumps. What better than those of the abundant oceanalgae?

Conventional farming methods produce higher yields at less expense. Isorganic farming really good for the environment? Matthew Fell, York

All kinds of farming are less good for the environment than naturalecosystems, such as forests, scrub and deserts. Organic farming might bebetter than agribusiness per hectare, but if it produces less food, moreland would be farmed and consequently there may be nothing to choose betweenorganic and agribusiness farming so far as the environment is concerned.

Is it true that you think that Gaia has always worked in our favour but thatwith climate change Gaia will work against us? Helen Barrington, Winchester

Gaia works in her favour and tries to keep a habitable planet. Mostcertainly she does not work specifically in our favour. When we doenvironmental damage we may disable Gaia's ability to help. Indeed, Gaia maynow be changing the Earth in a way unfavourable for us.

You have said that the UN's scientists are underestimating the speed ofclimate change in their official reports. Is that right? Chris Hastings,Dover

Yes, scientists who observe sea-level rise find it is happening about 1.6times faster than the Intergovernmental Panel on Climate Change predicted.Other observers find the rate of melting of floating ice in the North polarocean is happening faster than predicted. Just now we are long on theory andshort on observations.

If we are past the point of no return, what should we do? Edward Farmer,Pickering

If we are beyond the point of no return, then our greatest efforts should gotowards adapting and making sure that we survive as a species. Beyond thismythical tipping point it would be too late to try to stop global heating.If we have not yet reached the tipping point, I still think that we shouldconcentrate on adapting and surviving. We are not good at working togetherto reduce land use and CO2 emissions, and there may be little time left inwhich to do it.

Why are you so much in favour of nuclear power as a solution? Doesn't ithave lots of dangers? Hatty Hamilton, Exeter

I am in favour of nuclear energy for small, densely populated nations suchas the UK, Germany, France, others in Europe, and Japan. Such nations needan abundant supply of electricity to continue civilised life, and there isno alternative to nuclear energy; we used to use coal, gas and oil but nowknow we cannot. Nuclear energy also happens to be the safest, the mosteconomical and reliable of energy sources. It is foolish to reject it. Itssafety record in the UK – and we are not the best – is a vast improvementover that of coal, gas or oil. Remember over 5,000 people died in one nightin London in the 1950s from coal-smoke poisoning. Apart from water power andsolar energy in desert nations, renewable energy is inefficient, expensiveand unreliable, but with huge subsidies it makes a great deal of money forits developers. Most arguments against nuclear energy are propaganda and itis well worth asking who benefits from the flood of misinformation.

Why do you attack the green movement so much? Aren't you a green yourself?Howard James, Manchester

Yes, I am a green but, not surprisingly, an old-fashioned one. My differencewith the modern greens is mainly over their failure to see that thecountryside has intrinsic value for wildlife, for food supply and as parkland for our ever more urban society. The countryside should not be regardedas an industrial site for wind or solar energy. I also dislike the rampantignorance of science shown by modern greens, especially the idiotic way theyclass all chemicals as bad. We are all made from a mixture of chemicals andnot from some mysterious spiritual brew. Nuclear power is fantastically expensive – no nuclear power plant has eversurvived without vast sums of public money subsidising it.

Aren't yourwell-publicised positions just playing into the hands of the well-financednuclear lobby? David Lowe, Whitehaven

Nuclear power is not more costly than coal power. It could be much lessexpensive than coal, but has been made expensive by the prolonged legal andpolitical objections that confront all attempts to build a new nuclear powerstation. It is nonsense to suggest that there is a wealthy nuclear energylobby. The nuclear fuel industry is tiny compared with the coal, oil and gasindustries, and small compared with the renewable energy industry. The smallsize of the nuclear fuel industry is because one gram of uranium can deliveras much energy as a ton of coal or oil. If uranium were as costly as gold itwould barely affect the price of electricity.

Why are you so hostile to renewable energy in general and wind power inparticular? Norma Jones, Halifax

Mainly because they do not work under north European conditions and becausethey have become, through the abuse of subsidies by the greedy, a scam. Ilike the idea of solar thermal energy in nations with sunlit deserts, andwind energy in places where the wind blows constantly and few people live.

Where do you go to escape? Mary Plant, Plymouth

I would love to know where to go. Just now I am far too busy to escape. Ourholidays are in the South West, mostly walking.

You are determined to leave the planet and "see the face of Gaia" on one ofRichard Branson's strange-looking rockets. Isn't that environmentallydamaging? David Christopher, Birmingham

Probably no more damaging than driving from Devon to London and back a fewtimes or flying to Majorca every summer. If by seeing Gaia from SirRichard's spacecraft I can give a better account of Gaia, it will have beenworthwhile.

You once wrote that, as a result of global warming, "billions of us will die and the few breeding pairs of people that survive will be in the Arctic,where the climate remains tolerable". How should we choose the breedingpairs? Louise Smith, Hamilton

The Earth is already selecting the survivors. Those that move to a saferplace when life gets tough are likely to survive. We are not clever enoughto judge who should survive and should not try. But we may have to chosewhen faced by the awful question, who you allow aboard the lifeboat whenthere is room for only one more?

You're nearly 90. What ambitions do you have left? Henry Allen

To enjoy life to the full while I still can.