Martin Rees “The World in 2050”, 23^rd May 2009

Martin Rees is the Royal Astronomer. He gave a speech which summed up his view of the world in 2050. He had some interesting things to say about possible directions for science and technology in the 21^st century, but these notes are restricted to what he had to say about risks.

Barring a catastrophe the world population is forecast to be 9 billion by 2050. In 1950 Europe had 3 times the population of Africa. In 2050 the population of Africa will be 3 times the population of Europe. Up to now the predictions of Malthus have been proved wrong, thanks to the Green Revolution. However, Malthus may be vindicated in Africa.

Climate change: it is the small chance of a very big temperature shift that should motivate action. The main downsides to climate change lie in the future. We should not use a discount rate that is too high, otherwise we insufficiently take account of the future. We need urgency in addressing rising emissions. Unless the rising curve of emissions can be turned around by 2020, the amount will eventually reach a
threatening level.

Currently the safe target for emissions is projected to be 2 tons annually per person as a global average. Currently each US citizen causes 20 tons of emissions, each European 10 tons and each Chinese 4 tons.

Much more research on clean energy is needed. The American journalist Tom Freidman, in his book “Hot, Flat and Crowded” noted that currently Americans spend more on pet food than they spend on energy research. There is cause for optimism in the fact that President Obama has put together a dream team. There is some progress in the UK but it is not commensurate with the scale of the challenge. This problem should be accorded the urgency that was given to the Apollo or Manhattan projects. A DC grid
connecting the whole of Europe is needed, connected to the Sahara to gather solar energy for electricity, but this is 50 years away. Carbon capture and storage is very important – the developing world can leapfrog old technologies, as they have done in skipping landlines and moving straight to mobile phones.

Nicholas Stern has said that beating climate change can be achieved by spending 1 or 2 percent of  GDP.

If we do not tackle this problem we may end up with an Age of Stupid scenario. We should contemplate plan B if we cannot tackle emissions quickly enough. For example, adding aerosols to the air to block out the sun. But at best this will buy some time, and it will not stop the sea becoming acidic. It may also become another pretext for international disputes.

In our day to day lives we are safer and more comfortable than we have ever been. However, we are dependent on elaborate networks: E.g. the electricity grid, air traffic control, the internet. It is crucial to increase the resilience of these networks.

In our time we have confused attitudes to risk. We worry about train crashes which are rare. But we are in denial about other risks e.g. pandemics. We should apply an insurance based approach to risks. That is to value a risk at the probability of occurrence multiplied by the cost of the event.

There is an arms race between prevention and pathology. Biotechnology may empower small groups to do great harm. The global village has its idiots.

Food  and energy security and climate change and global pandemic are key risks. Also, by 2050 the biosphere may be ravaged. There have been 5 great extinction events in the history of the Earth. The  extinction rate is currently 1000 times higher than normal and is increasing. We are destroying the book of life before we have read it. We have entered a new age, the Anthropocene. As well as preserving the richness of the biosphere for the benefit of humans, we should preserve it for its own sake.

There is a military dictum that one should always prepare for the worst case. Why should this be different for the security of the planet? This was a quote by Prince Charles.

There followed an interesting discussion of the possible future of scientific discovery. For example, it is possible that humans could make a super intelligent machine, that would be the last machine we ever make, because it will be able to build future machines. Also, he mentioned that there may be limits to science in that our brains may not be good enough to understand everything – there is no reason
to think that our brains are matched to see the secrets of the world. There is a widening gulf between what scientists can do and what they should do. People are generally positive about science, but they might not be in future. There are alternative bad images of scientists e.g. Frankenstein, Moreau, Strangelove. Choices of how science is applied should not be left only to scientists. Everyone needs to have a feel for science and risk, so we can have a proper debate. Scientists should not be indifferent to their creations.

This century is special. This is the first time that one species has the capability to jeopardise not only its own future but also life’s great potential. When Apollo 8 orbited the moon, it took an iconic picture of the Earth rising against the moon. Sustaining the future of life on Earth is imperative.

Suppose aliens had been watching the Earth from its beginning over 4 billion years ago. For more than 99.99% of its history it has been subject to gradual change. Then, in the sliver of time over the last 1000 years, patterns of vegetation have changed. The pace of change has accelerated and become more abrupt over the last 50 years. The concentration of carbon dioxide has risen very fast. The planet has started emitting radio waves. Projectiles have been sent out of Earth’s atmosphere. The aliens could confidently predict that the Earth would face its doom in a few billion years, with the decline of the sun. Would they have predicted the sudden fever of the Earth that is occurring? If they continue to watch us, will they see a sudden spasm, followed by silence?

The outcome depends upon policy choices. The policy choices that are made will be guided by effective and idealistic scientists.

I raised the issue regarding climate change – that science is objective whereas climate change involves making subjective judgements about what is too much risk. I asked what he would say to a scientist would was worried about compromising his objectivity by acting as an advocate on climate change. He replied by saying that there is a large degree of uncertainty in climate science. We need to plan for the worst case.