Sir David King on Climate Change

On Friday, I saw Sir David King talk about his new book on climate change: ‘The Hot Topic‘. He came across as you’d expect: warm, authoritative, knowledgeable – the antithesis of ignorance.

One way to measure the advances made in the twentieth century is to look at the life expectancy, which has gone up from around 45 at the start of the 20th century to around 80 at the end. Women’s fertility has dropped as well – In the last 10 years the fecundity has gone down in Latin America from 5.5 to 2. But the population growth is still a given. at over 9 billion by the middle of the century.

It is this population growth that is causing our problems. The challenges of the 21st century: food, water, energy, security, disease etc. are strongly linked together – and climate change is a common factor.

One of the key policy tools for solving the problem is *forward looking regulation*. For example, telling car manufacturers that cars must be of a certain standard. Johnson Matthey – a local company – in fact even now makes very efficient catalytic converters. The air comes out cleaner than it goes in!!

After all this regulation of local pollutants you are simply left with CO2 is a colourless, odourless gas. Safe of course. But of course it has serious effects.

Look at the relation between CO2 and temperature. We know the temperature was at the Palaeocene-Eocene maximum about 8-10 warmer than it is now.

This has huge impacts, not least on biodiversity. The mountain gorillas of central Africa need 40 or so plants to survive, and lives in a specialised bamboo forest. The gorillas move with the – isotherms up the mountain but eventually they reach the top of the mountain and there is nowhere to run to. We’re not capable of recreating their natural habitat.

One difficulty is negotiating with so many countries that are in different current and historical states. e.g. US & Canada pollute twice as fast as Europe.

However we must involve the developing world too – as a graph of projected future BAU emissions shows. To reduce carbon emissions to safe levels, emissions need to peak at about 9GtC in next 10 years for 450ppmCO2only and about 12GtC per an in next 20 years for 550ppmCO2only. This is a huge task. But we’d better start now!

In short then, climate change is ‘The Hot Topic‘!