Peter Schwartz highly recommended this book when we met for dinner last week. It has been a mind blowing journey traversing ecology, urbanisation, climate change, transgenic crops, nuclear energy and geoengineering. We don’t have to agree on everything, but we must think carefully through these issues, and be prepared to change our minds as new information emerges.

Last week, I attended an informal ministerial meeting on climate change in Pretoria, South Africa, and experienced first hand the enormous difficulties the negotiators are facing.

The crux of the negotiations is to achieve the stabilisation of greenhouse gas concentration in the atmosphere. The current goal is to limit the rise of global temperatures to less than 2 degrees centigrade. This is the level that the scientists have told us is necessary to avoid catastrophic climatic instability. However, there is currently a big gap between this goal and the current pledges by the international community. The United Nations Environment Programme Report published last year indicated a clear gap of at least 5 gigatonnes of carbon dioxide per year even in the best case scenario.