Climate Change

The hon. Gentleman is absolutely right. Whatever agreement is struck at Copenhagen, one issue for the future will be compliance and what we do in cases of non-compliance. There are not, in truth, easy answers to that. That point leads me on to address the core of the deal that we are looking for, about which I think hon. Members on both sides of the House agree. Ambition is important. We must get on a 2° trajectory. Lord Stern has come up with rather interesting numbers on this, which suggest that the world is currently emitting about 50 gigatonnes, and we should be seeking to get on a pathway leading to about 18 gigatonnes by 2050. To get on that pathway, we need to be at 44 gigatonnes by 2020. That is a good benchmark for thinking about the agreement we are seeking, although we will have to see whether we will get all the way to 44 gigatonnes. Lord Stern says—this is why there is a little cause for optimism—that the pledges already on the table take us down to 48 gigatonnes. That reduction might not sound like very much, but it should be noted that we would expect the numbers to rise to between 55 and 60 gigatonnes if people were carrying on with business as usual. We need to go further, however—we need to have the ambition to do so. That will have to come from actions by countries, finance for developing countries, and succeeding in areas such as reducing deforestation.