Matt Ridley: How Global Warming Can Be Good For Us

Global warming is real. It is also – so far – mostly beneficial. This startling fact is kept from the public by a determined effort on the part of alarmists and their media allies who are determined to use the language of crisis and emergency. The goal of Net Zero emissions in the UK by 2050 is controversial enough as a policy because of the pain it is causing. But what if that pain is all to prevent something that is not doing net harm?

The biggest benefit of emissions is global greening, the increase year after year of green vegetation on the land surface of the planet. Forests grow more thickly, grasslands more richly and scrub more rapidly. This has been measured using satellites and on-the-ground recording of plant-growth rates. It is happening in all habitats, from tundra to rainforest. In the four decades since 1982, as Bjorn Lomborg points out, NASA data show that global greening has added 618,000 square kilometres of extra green leaves each year, equivalent to three Great Britains. You read that right: every year there’s more greenery on the planet to the extent of three Britains. I bet Greta Thunberg did not tell you that.

The cause of this greening? Although tree planting, natural reforestation, slightly longer growing seasons and a bit more rain all contribute, the big cause is something else. All studies agree that by far the largest contributor to global greening – responsible for roughly half the effect – is the extra carbon dioxide in the air. In 40 years, the proportion of the atmosphere that is CO2 has gone from 0.034 per cent to 0.041 per cent. That may seem a small change but, with more ‘food’ in the air, plants don’t need to lose as much water through their pores (‘stomata’) to acquire a given amount of carbon. So dry areas, like the Sahel region of Africa, are seeing some of the biggest improvements in greenery. Since this is one of the poorest places on the planet, it is good news that there is more food for people, goats and wildlife.

But because good news is no news, green pressure groups and environmental correspondents in the media prefer to ignore global greening. Astonishingly, it merited no mentions on the BBC’s recent Green Planet series, despite the name. Or, if it is mentioned, the media point to studies suggesting greening may soon cease. These studies are based on questionable models, not data (because data show the effect continuing at the same pace). On the very few occasions when the BBC has mentioned global greening it is always accompanied by a health warning in case any viewer might glimpse a silver lining to climate change – for example, ‘extra foliage helps slow climate change, but researchers warn this will be offset by rising temperatures’.

Another bit of good news is on deaths. We’re against them, right? A recent study shows that rising temperatures have resulted in half a million fewer deaths in Britain over the past two decades. That is because cold weather kills about ’20 times as many people as hot weather’, according to the study, which analyses ‘over 74million deaths in 384 locations across 13 countries’. This is especially true in a temperate place like Britain, where summer days are rarely hot enough to kill. So global warming and the unrelated phenomenon of urban warming relative to rural areas, caused by the retention of heat by buildings plus energy use, are both preventing premature deaths on a huge scale.

Surely this will change in the future? Probably not. Britain would have to get much, much hotter for summer mortality to start exceeding winter deaths. Not even Greece manages that. And the statistics show that – as greenhouse-gas theory predicts – on the whole more warming is happening in cold places, in cold seasons and at cold times of day. So winter nighttime temperatures in the global north are rising much faster than summer daytime temperatures in the tropics.

Summer temperatures in the US are changing at half the rate of winter temperatures and daytimes are warming 20 per cent slower than nighttimes. A similar pattern is seen in most countries. Tropical nations are mostly experiencing very slow, almost undetectable daytime warming (outside cities), while Arctic nations are seeing quite rapid change, especially in winter and at night. Alarmists love to talk about polar amplification of average climate change, but they usually omit its inevitable flip side: that tropical temperatures (where most poor people live) are changing more slowly than the average.

But are we not told to expect more volatile weather as a result of climate change? It is certainly assumed that we should. Yet there’s no evidence to suggest weather volatility is increasing and no good theory to suggest it will. The decreasing temperature differential between the tropics and the Arctic may actually diminish the volatility of weather a little.

Indeed, as the Intergovernmental Panel on Climate Change (IPCC) repeatedly confirms, there is no clear pattern of storms growing in either frequency or ferocity, droughts are decreasing slightly and floods are getting worse only where land-use changes (like deforestation or building houses on flood plains) create a problem. Globally, deaths from droughts, floods and storms are down by about 98 per cent over the past 100 years – not because weather is less dangerous but because shelter, transport and communication (which are mostly the products of the fossil-fuel economy) have dramatically improved people’s ability to survive such natural disasters.

The geological record shows greater climatic volatility in cold periods of the Earth’s history than in hot periods. At the peak of recent ice ages, the temperature fluctuated dramatically between years and decades, while decade-long mega-droughts ravaged Africa, drying up Lake Victoria at least twice. Those mega droughts happened 17,000 years ago and 15,000 years ago respectively, when the world was much colder than today and cooler oceans meant failed monsoons. One theory about the invention of farming argues that it was impossible until the climate settled down in the post-glacial warmth of around 10,000 years ago: ‘Recent data from ice- and ocean-core climate proxies show that the last glacial climates were extremely hostile to agriculture – dry, low in atmospheric CO2, and extremely variable on quite short time scales.’ It then became calmer as it became significantly warmer than today between 9,000 and 6,000 years ago, when human civilisation emerged.

The effect of today’s warming (and greening) on farming is, on average, positive: crops can be grown farther north and for longer seasons and rainfall is slightly heavier in dry regions. We are feeding over seven billion people today much more easily than we fed three billion in the 1960s, and from a similar acreage of farmland. Global cereal production is on course to break its record this year, for the sixth time in 10 years.

Nature, too, will do generally better in a warming world. There are more species in warmer climates, so more new birds and insects are arriving to breed in southern England than are disappearing from northern Scotland. Warmer means wetter, too: 9,000 years ago, when the climate was warmer than today, the Sahara was green. Alarmists like to imply that concern about climate change goes hand in hand with concern about nature generally. But this is belied by the evidence. Climate policies often harm wildlife: biofuels compete for land with agriculture, eroding the benefits of improved agricultural productivity and increasing pressure on wild land; wind farms kill birds and bats; and the reckless planting of alien sitka spruce trees turns diverse moorland into dark monoculture.

Meanwhile, real environmental issues are ignored or neglected because of the obsession with climate. With the help of local volunteers I have been fighting to protect the red squirrel in Northumberland for years. The government does literally nothing to help us, while it pours money into grants for studying the most far-fetched and minuscule possible climate-change impacts. Invasive alien species are the main cause of species extinction worldwide (like grey squirrels driving the red to the margins), whereas climate change has yet to be shown to have caused a single species to die out altogether anywhere.

Of course, climate change does and will bring problems as well as benefits. Rapid sea-level rise could be catastrophic. But whereas the sea level shot up between 10,000 and 8,000 years ago, rising by about 60 metres in two millennia, or roughly three metres per century, today the change is nine times slower: three millimetres a year, or a foot per century, and with not much sign of acceleration. Countries like the Netherlands and Vietnam show that it is possible to gain land from the sea even in a world where sea levels are rising. The land area of the planet is actually increasing, not shrinking, thanks to siltation and reclamation.

In January 2020, the UK’s chief scientific adviser organised for some slides to be shown to Boris Johnson to convert him to climate alarmism. Thanks to a freedom of information request, we now know that these slides showed the likely acceleration in sea-level rise under a scenario known as RCP 8.5. This is shocking because RCP 8.5 has long been discredited as a highly implausible future. It was created by piling unrealistic assumptions on to each other in models: coal use increasing tenfold by 2100, population growth accelerating to 12 billion people, innovation drying up and an implausibly high sensitivity of temperature to carbon dioxide. No serious scientist thinks RCP 8.5 represents a likely outcome from ‘business as usual’. Yet those who want to grab media attention by making alarming predictions use it all the time.

Environmentalists don’t get donations or invitations to appear on the telly if they say moderate things. To stand up and pronounce that ‘climate change is real and needs to be tackled, but it’s not happening very fast and other environmental issues are more urgent’ would be about as popular as an MP in Oliver Cromwell’s parliament declaring, ‘The evidence for God is looking a bit weak, and I’m not so very sure that fornication really is a sin’. And I speak as someone who has made several speeches on climate in parliament.

No wonder we don’t hear about the good news on climate change.

Matt Ridley, a member of the British House of Lords, is an acclaimed author who blogs at www.rationaloptimist.com.