A four degree world

In the last fortnight several things have occurred which are deeply troubling. The floods in southern Taiwan (Typhoon Morakut) have been followed by very heavy rain in the northern Philippines (and there is another storm there right now), and record flooding in Karnataka, India. These events are very likely to have adverse agricultural effects and hence harm nutrition and health. The number of hungry on the planet has passed a billion. Climate change is a likely cause. In the short run the Sumatran earthquake and the Samoan tsunami have distracted attention, but climate change has not gone away.

We have also had the Oxford conference on a 4 degree world (to which we contributed a paper about health).  The podcast there called "4°C of climate change: alarmist or realist?" is very good; the conclusion was that an 8 degree world is alarmist, but a 4 degree world is all too plausible. As one participant said: we see a 70 kg person climb into a 1,000 kg car to drive two miles in order to collect a newspaper - and then we want to fix the problem with geo-engineering! (The most plausible form of geo-engineering is to pump large quantities of sulphur into the atmosphere, which may harm the monsoon.)

On the positive side, this morning I participated electronically in an electronic conference held by PAHO (the Pan American Health Organisation) using elluminate software. It was great. In real time I could hear, see powerpoint slides, and send short messages and symbols (eg smile, applause) to other participants (10 English, 70 Spanish).

On the negative side, I just heard Ian MacFarlane, that gravelly voiced member of the Australian opposition, go on about the alleged harm to the Australian economy if we were to take tiny baby steps in reducing our use of fossil fuel. The short and narrow sightedness of so many people in this country (because let's face it, MacFarlane etc represent a great number of Australians) is shameful. The 4 degree conference warns of carbon dioxide levels of 700 ppm or more by 2100. With it will go crop failure, marked sea level rise and millions of environmental refugees. This is a terrifying future – and not far away.

One commentator at the 4°C conference, a journalist, warned that too much emphasis on catastrophe was paralyzing. But others pointed out that we can go too far in the other direction, and that just fuels complacency. A consensus seemed to emerge that scientists must try to convey the full picture, as far as possible.

I also spoke this morning on ABC overnight talk back radio http://www.abc.net.au/overnights/ for 30 minutes (60 channels throughout Australia) about population. Almost every caller thought we have a problem. One asked why population is scarcely mentioned in the context of climate change. I think he had a very good point – but while only a small fraction (maybe 20%) of the global population contribute substantially to climate change there are three reasons to be concerned about the fertility rate of the other 80%. First, rapid population growth in poor countries will make those countries more vulnerable to climate change. Second, in the long run, the climate contribution of several billion poor people is still significant – especially if they do start to want and to afford our kind of lifestyle. Finally, the acceleration of the demographic (fertility) transition in the South (low income countries) is a matter of justice and global human rights. See too our paper on this in the Bulletin of the World Health Organisation (Climate change and family planning: least developed countries define the agenda).