The scientific consensus is that moderate warming does more good than harm
Climate change has done more good than harm so far and is likely to continue doing so for most of this century. This is not some barmy, right-wing fantasy; it is the consensus of expert opinion. Yet almost nobody seems to know this. Whenever I make the point in public, I am told by those who are paid to insult anybody who departs from climate alarm that I have got it embarrassingly wrong, don’t know what I am talking about, must be referring to Britain only, rather than the world as a whole, and so forth.
At first, I thought this was just their usual bluster. But then I realised that they are genuinely unaware. Good news is no news, which is why the mainstream media largely ignores all studies showing net benefits of climate change. And academics have not exactly been keen to push such analysis forward. So here follows, for possibly the first time in history, an entire article in the national press on the net benefits of climate change.
There are many likely effects of climate change: positive and negative, economic and ecological, humanitarian and financial. And if you aggregate them all, the overall effect is positive today — and likely to stay positive until around 2080. That was the conclusion of Professor Richard Tol of Sussex University after he reviewed 14 different studies of the effects of future climate trends.
To be precise, Prof Tol calculated that climate change would be beneficial up to 2.2˚C of warming from 2009 (when he wrote his paper). This means approximately 3˚C from pre-industrial levels, since about 0.8˚C of warming has happened in the last 150 years. The latest estimates of climate sensitivity suggest that such temperatures may not be reached till the end of the century — if at all. The Intergovernmental Panel on Climate Change, whose reports define the consensis, is sticking to older assumptions, however, which would mean net benefits till about 2080. Either way, it’s a long way off.
Now Prof Tol has a new paper, published as a chapter in a new book, called How Much have Global Problems Cost the World?, which is edited by Bjorn Lomborg, director of the Copenhagen Consensus Centre, and was reviewed by a group of leading economists. In this paper he casts his gaze backwards to the last century. He concludes that climate change did indeed raise human and planetary welfare during the 20th century.
You can choose not to believe the studies Prof Tol has collated. Or you can say the net benefit is small (which it is), you can argue that the benefits have accrued more to rich countries than poor countries (which is true) or you can emphasise that after 2080 climate change would probably do net harm to the world (which may also be true). You can even say you do not trust the models involved (though they have proved more reliable than the temperature models). But what you cannot do is deny that this is the current consensus. If you wish to accept the consensus on temperature models, then you should accept the consensus on economic benefit.
Overall, Prof Tol finds that climate change in the past century improved human welfare. By how much? He calculates by 1.4 per cent of global economic output, rising to 1.5 per cent by 2025. For some people, this means the difference between survival and starvation.
It will still be 1.2 per cent around 2050 and will not turn negative until around 2080. In short, my children will be very old before global warming stops benefiting the world. Note that if the world continues to grow at 3 per cent a year, then the average person will be about nine times as rich in 2080 as she is today. So low-lying Bangladesh will be able to afford the same kind of flood defences that the Dutch have today.
The chief benefits of global warming include: fewer winter deaths; lower energy costs; better agricultural yields; probably fewer droughts; maybe richer biodiversity. It is a little-known fact that winter deaths exceed summer deaths — not just in countries like Britain but also those with very warm summers, including Greece. Both Britain and Greece see mortality rates rise by 18 per cent each winter. Especially cold winters cause a rise in heart failures far greater than the rise in deaths during heatwaves.
Cold, not the heat, is the biggest killer. For the last decade, Brits have been dying from the cold at the average rate of 29,000 excess deaths each winter. Compare this to the heatwave ten years ago, which claimed 15,000 lives in France and just 2,000 in Britain. In the ten years since, there has been no summer death spike at all. Excess winter deaths hit the poor harder than the rich for the obvious reason: they cannot afford heating. And it is not just those at risk who benefit from moderate warming. Global warming has so far cut heating bills more than it has raised cooling bills. If it resumes after its current 17-year hiatus, and if the energy efficiency of our homes improves, then at some point the cost of cooling probably will exceed the cost of heating — probably from about 2035, Prof Tol estimates.
The greatest benefit from climate change comes not from temperature change but from carbon dioxide itself.
Facts & hard data available in Richard Tol’s paper