An awkward aspect of climate alarmism is that warming supposedly brings ecological disaster on a broad front, and supposedly warming is upon us. So there ought to be mass extinctions, desertification and unhappiness. Yet the planet has greened dramatically in the past half-century, dramatically boosting agriculture in poorer countries, almost as though plants like warmth and CO2 as much as their ancestors did back when it was much warmer, CO2 levels were much higher and giant beasts roamed lush landscapes. For some time alarmists ignored or denied the phenomenon. But now that it’s inescapable, they say well, too bad, it’s all coming to an end and of course doom looms: “Nature's capacity to sequester carbon is decreasing and with it society's dependence on future strategies to curb greenhouse gas emissions is increasing”. There is no good news in climate alarmism. There mustn’t be.
The study in Science, by researchers at CREAF and the University of Nanjin, says that plants can’t keep growing indefinitely on CO2 alone. As one of the lead researchers put it, “plants need CO2, water and nutrients in order to grow. However much the CO2 increases, if the nutrients and water do not increase in parallel, the plants will not be able to take advantage of the increase in this gas”. Which is sort of true. But only sort of.
In the first place, all else being equal, it’s good to have more of an essential requirement even if it yields diminishing returns. In the second, farmers will be happy to supply other nutrients. And unless we missed something, a fertile climate generates more nutrients because, as that famous climate activist and non-scientist Prince Charles once put it, “Our planet and its ecosystems run through cycles and loops, for example the water cycle and carbon cycle. Soils break down plant remains and turn them into the nutrients needed to grow new plants. As is common sense, everything is recycled and reused: in Nature there is no waste.”
Oddly, he felt that nature would scorn to use human CO2; being outside nature it would be wasted. But never mind. Let’s talk about that water cycle.
The Science paper warned that the beneficial effects of CO2 would diminish without more water. (OK, it said they would reverse and our hair would catch fire. But let’s keep calm here.) And as far as it goes it’s true although as noted above diminishing isn’t the same as stopping let alone reversing. But aren’t we meant to get more water with warming? More rain, more flooding, rising seas?
Ah but nay. As usual with climate alarmism, we only get more water where there’s already too much. We get less where there’s already too little. And it would be nitpicking to observe that a major aspect of the recent greening is precisely the improved fertility of marginal arid regions because when plants need fewer stomata to absorb CO2, they also lose less water. The big point is that once again, the history of the Earth does not support this contention.
Take any period you like when it was warm and atmospheric CO2 was high. Do you find a wasteland of deserts and bogs? Of course not. Nor do you see one on the planet today where after a century and a half of warming, most of it natural, and rising atmospheric CO2, there’s been a dramatic expansion of the green stuff and a shrinking of the brown and grey.
To announce that clearly the process is about to reverse because the laws of nature are constant including that all effects of warming are bad and all bad effects are due to warming is, well, more of the same. And we don’t mean it in a good way.
Some studies show that adding CO2 increases plant growth without increase in water because of less water loss through stomata.