James Lovelock delivers dire prediction to humanity about fate of planet

A speech given by Professor James Lovelock at IChemE’s 5th John Collier Memorial Lecture, Savoy Place, London, 28th November 2006.

… The history of global heating 55 million years ago suggests that the injection of gaseous carbon compounds took place over a period of about 10,000 years, much slower than we are now doing. In his paper, Professor Elderfield suggests that because of the slow rate of introduction CO2 rose by no more than 70 and 160 ppm. Compared with our present pollution with CO2 this is a small increase, we have already raised CO2 by 100 ppm with an injection of only 500 Gigatons. In thirty years, if we continue business as usual, we will have added 1000 Giga tons and raised CO2 by 200ppm, more than is thought to have been present in the early Eocene. The great rapidity of our pollution of the atmosphere with carbon gases is as damaging as is the quantity. The rapidity of our pollution gives the Earth system little time to adjust and this is particularly important for the ocean
ecosystems; the rapid accumulation of CO2 in the surface water is making them too acid for shell forming organisms. This did not happen during the Eocene event because there was time for the more alkaline deep waters to mix in and neutralize the surface ocean.

…There are other differences between the earth 55 M yrs ago and now. It was about three degrees warmer at the start of the event and it took place on an Earth with a more uniform temperature than now. The polar ocean was a land locked fresh water lake. There were no ice caps and the sea was about 200 metres higher than now. On the other hand the sun was 0.5% cooler and there was no agriculture anywhere so that natural vegetation was free to regulate the climate. Another
difference was that the world was not then experiencing global dimming – the 2 to 3 degrees of global cooling caused by the atmospheric aerosol of man made pollution. This haze that covers much of the Northern hemisphere offsets global heating by reflecting sunlight. The aerosol particles of the haze persist in the air for only a few weeks, whereas carbon dioxide persists for between 50 and 100 years. Any economic downturn or planned cut back in fossil fuel use, which lessened the aerosol density, could carry us beyond the threshold of irreversible change. This is why I say we live in a fool’s climate. We are damned if we continue to burn fuel and damned if we stop too suddenly.

The entire speech:

IChemE (PDF)