It is important that we follow Sir Nicholas Stern's advice. My hon. Friend is right that his findings, which I do not think have been disputed by any serious commentator, are that unless we are prepared to make the necessary investment now to tackle climate change, we will pay a heavy price in terms of loss of GDP not just in our country, but across the world. The Government will keep that under continuous review, and the sums that we are spending on tackling climate change are reflected in the additional money that has been given to Departments right across the piece. She is right that we must make the necessary investment over the next few years if we are to tackle climate change and ensure economic growth in the future.