asked Her Majesty’s Government:

What is their latest assessment of the future of climate change.

My Lords, an assessment of future climate change comes from the Intergovernmental Panel on Climate Change’s 2007 report. The global average temperature will rise between 1.1 and 6.4 degrees Celsius above 1990 levels by 2100 if greenhouse gas emissions continue unabated. Warming will be accompanied by rising sea levels, changes in rainfall patterns and more extreme whether. The UK Climate Impacts Programme scenarios project warmer, wetter winters and hotter, dryer summers with more extreme weather events and rising sea levels.

My Lords, I thank my noble friend for that reply. Does he agree that the case for long-term climate change is really not yet settled? In particular, is it not nonsense to predict the situation at the end of the century, as has been done? At the beginning of the 20th century, it was forecast that running out of coal would result in a cold climate for centuries to come. Should my noble friend accept that, in the words of the noble Lord, Lord Lawson, in the argument for global warming there is,

“a grain of truth and a mountain of nonsense”?

My Lords, as my noble friend knows, he asked the same Question on 16 October 2006; I think that his supplementary is very similar as well. My Answer was slightly different. The temperature ranges are slightly different, because the previous Answer was based on the 2001 Intergovernmental Panel on Climate Change report. This matter is being watched all the while.

With due respect to everybody else, there is considerable confidence around the world that the climate models provide reliable estimates of future climate change. This comes from the fact that the models use fundamental chemistry and physics, and not people’s hunches. For example, the first report of the IPCC in 1990 correctly projected the observed warming up to the present. The confidence in the model estimates is higher for some climate variables, such as temperature, but less so for others, such as precipitation.

The long-term warming trend due to greenhouse gases is there. That is mixed up with short-term variability that happens with our weather patterns in any event.

My Lords, I thank the noble Lord, Lord Sheldon, for his wholly unsolicited testimonial to my book. I also ask the Lords Minister of the year—I warmly congratulate him on that well deserved award—

Hear, hear.

My Lords, is the Minister not being a little over the top? I am sure that he is aware that the impact assessment of his own department, Defra, for the Climate Change Bill suggests that the cost to the British economy of the Bill’s absurd proposals for a 60 per cent decarbonisation—more may well be recommended—is £200 billion by 2050; many independent economists have put it much higher. The benefits—highly conjectural and dependent on a global agreement which is unlikely to arise in the form sought—are, at best, about half that. A different approach based on adaptation, should there be a problem—despite these models predicting increasing warming this century, there has been no further warming so far—

Question!

My Lords, should this not really go back to the drawing board?

My Lords, I am very grateful for the noble Lord’s initial comments and for the kind words he said about me last night, which I shall try to reciprocate now. The long-term warming trend is there. However, as regards the short term, figures show that there could have been a decrease in the past couple of years due to La Nina occurring in the Pacific Ocean—which the scientists say has finished this week—which is the cold aspect of it. That can have an effect on world water and land temperatures. However, the consensus of scientists is that the long-term trend of increased temperatures results from man-made emissions.

I am reluctant to say anything about the Climate Change Bill, which has started its Committee stage in the other place, and will come back to this House. I should not prejudge what the other place will do. However, according to the Stern report—which still remains the bible, whatever people may say about it—if we do not act, we will lose something like 5 per cent of global GDP each year now and for ever. The cost of action to reduce greenhouse gas emissions to avoid the worst impacts can be limited to around 1 per cent of global GDP per year. Therefore, we can still have growth and deal with climate change.

My Lords, we on these Benches agree with the Minister’s comments on the problem. However, when the Government came to power in 1997, they set themselves a target of a 20 per cent reduction in carbon dioxide by 2010. Yet over the past three years there has been no reduction whatever at 557 million tonnes. The figure is now higher than in 1997. When will carbon dioxide reductions start in the United Kingdom?

My Lords, I take the noble Lord’s point about emissions. The United Kingdom can set a lead on this but we cannot solve the problem ourselves. That is the whole point of the exercise. We can preach to others if we are doing something ourselves. We are only a small player in this. The noble Lord is right: the EU’s target was to limit global average temperatures to no more than 2 degrees above pre-industrial levels. That would require CO₂ concentrations to be stabilised at or below 500 parts per million. The concentration is already about 430 parts per million and the models used by the Henley Centre warn that an even lower level is required. We are on course to meet our Kyoto commitments along with most other member states of the European Union. However, overall, we have to do more in terms of adaptation and mitigation. That will not be pleasant, but it has to be planned so that we can take the population along with us.

My Lords, has my noble friend heard about or seen the reports published today which indicate that within the next decade there will be no ice in the Arctic in summer despite the fact that the winter seasons have been colder of late? Does he agree that the environmental impacts and the impacts on people’s lives of that trend are not yet fully understood and are things that we need to consider very seriously when thinking about climate change in the future?

My Lords, I have not seen the reports that my noble friend mentioned. However, it is reported that there could be catastrophic tipping points in the world’s climate, whether caused by thermal changes in the Atlantic or what is happening in the Arctic and the loss of the ice. On the other hand, none of these tipping points may occur. If they occurred, it would be catastrophic. In my original Answer I gave a range of temperatures, and if the upper range was reached none of us would probably be here. My noble friend is right to say that this is a serious business. The reason the Pacific’s temperatures are changing, and why we have just had La Nina as opposed to El Nino, is the flow of colder water from the depths and from the ice packs. I understand that that has been switched off, as it were, by nature this week. That will probably start to change the pattern and lead to slightly warmer temperatures. However, the change to which my noble friend referred is happening and we have to deal with it.