If we embrace within the next couple of years a decarbonisation target that is stricter than shale gas can help us to get to, I think that there will be a problem in the way of shale gas.
Perhaps I may turn briefly to climate change. This is not the time to re-fight the climate change debate, but others have brought it up. Given that shale gas offers the possibility of a slower rate of decarbonisation—not to as low a level of target as we are talking about—we need to retain the flexibility of that and to take into account where the climate change science has shifted to. It is simply not the case that the science has become more alarming in the past few years. There has been a series of studies of climate sensitivity in recent years by Otto et al., Aldrin et al., Ring and Searchinger and
many others. The biggest of those, the Otto et al. study, which had 14 leading authors, two of whom are co-ordinating lead authors of the Intergovernmental Panel on Climate Change, concluded that transient climate sensitivity—that is, the number that we are likely to reach in about 50 years—is about half of what we thought it was. It is about 1.3 degrees centigrade, of which we have had nearly half already. It is not true to say that we are seeing damaging effects on weather from climate change. Weather is not climate change. The Intergovernmental Panel on Climate Change SREX report in late 2011 came to the very firm conclusion that you could not see a signal of climate change in current climate events, neither in droughts, floods, storms nor any of those kinds of things. Professor Roger Pielke at the University of Colorado has come to exactly the same conclusion. There is no evidence yet that we are seeing damage. Meanwhile, we are seeing clear damage from climate change policies. The denial of cheap electricity to people in poor countries and the effect of biofuels on food prices are having a demonstrable effect on both hunger and well-being in other parts of the world. We have to take these things into account.
I hasten to add that I accept the science of climate change. By that, I mean I accept that carbon dioxide has its full greenhouse effect. At Second Reading, the noble Lord, Lord Prescott, said that I was denying this, but I accept that it has the full effect. However, the full effect is only 1.2 degrees centigrade warming for a doubling of the quantity of carbon dioxide—it is there in section 8.6.2.3 of the latest report of the Intergovernmental Panel on Climate Change. The danger arises from the potential feedback effects from water vapour in the atmosphere. We can measure whether those are happening and it is clear they are happening more slowly than expected—that is what those papers I cited are all about.
This is not about saying that climate change is or is not happening; it is about saying that potentially the world is changing. We are finding flexibilities in the way in which the world is changing which mean that we should retain flexibility in policy. That is why I oppose the amendment.