Professor Peter Stott:

Let me address that with a remark from a scientist working with other scientists, but in a different national context. I have done a lot of work in the past few years with Chinese scientists, not just around the attribution science but around the whole area of climate science, as part of a collaborative project I am involved in. It has been very interesting for me to learn a little about the context in China, and to meet some academics talking about the challenges, and to meet colleagues from the Chinese meteorological administration. What I learned there is that China is facing some very significant challenges around, for example, food security - feeding its population - and issues to do with flooding and drought. Chinese scientists have been writing very important papers about how climate change is changing the risk of these extreme weather events. It is clear to me, as a scientist, that the Government in China takes these threats of climate change to its population very seriously. I take that to mean that when China engages in this international political discussion, it is taking that evidence and those impacts on board. This is in the context of looking across the globe, and seeing some countries feeling the benefits from climate change. That may be the case but if one looks across the world, it is probably true to say that the great majority of countries have very significant challenges, including the example I have given of China. While China clearly has its own policies, which I will not go into, one of the issues it is addressing is the issue of its population. This is a serious issue, and it is true of many places.

On the impacts, one of the things the scientific evidence is showing is that many of the areas in the tropics are significantly affected by climate change. These are countries that are very poor and vulnerable. There are very big challenges there. That is something we need to stress because if we think of drought, in particular, the signal of climate change is rather large, relative to the variations in those place in the tropics. The hazard is large there, as is the vulnerability, and therefore, the impact is also.

Impacts, including deleterious ones, are being felt in many parts of the world. One obvious positive benefit is the potential in some northern high latitudes for crops. Studies have looked at that and looking at the global picture, they have concluded that, in the context of continued emissions, it is very clear the net effect is a negative impact.