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.
