Tuesday 27 April 2021

Is farm productivity already declining due to climate change?

 

Is farm productivity already declining due to climate change?


Climate alarmists would have you believe that climate change is already hurting farm productivity. But hasn’t farm productivity been relentlessly rising?

One of the leading climate alarmist publications in the world, The Guardian, published a shocking headline recently: ‘Rapid global heating is hurting farm productivity, study finds’.

At first, it seems like an April Fool’s joke. After all, it had been published on 1 April, and everyone knows farm productivity is relentlessly rising.

Upon reading it, however, one realises that the publication is deadly serious about this.

I call The Guardian ‘alarmist’ not because I like throwing pejoratives around. It is alarmist because it colludes with 400 other publications to employ ever more severe, value-laden words to describe climate change.

The latest addition to the propaganda arsenal, also adopted by publications such as Scientific American, is the term ‘climate emergency’ used in lieu of ‘climate change’. It also recently replaced ‘global warming’ with ‘global heating’.

With reported average global surface temperatures a mere 1°C above 1880 levels, of which human activity is supposedly responsible for about half, there hardly seems much justification for such superlatives. Their use firmly takes The Guardian and its co-conspirators out of the journalism camp and into outright ideological advocacy.

Try challenge even just one aspect of their climate change narrative, and see where that gets you, these days.

It is not surprising, then, that The Guardian is pulling out all the stops to demonstrate that we really are in an emergency. Besides yelling ‘climate change’ (or rather, ‘climate emergency!’) every time there’s some bad weather or a fire, the latest attempt to do so turns everything we thought we knew about agriculture on its head.

‘The climate crisis is already eating into the output of the world’s agricultural systems,’ The Guardian’s Oliver Milman wrote, ‘with productivity much lower than it would have been if humans hadn’t rapidly heated the planet, new research has found.’

The research, according to the article, says that farm productivity ‘has actually slumped by 21% since 1961, compared to if the world hadn’t been subjected to human-induced heating.’

Clever rhetorical trick

Arguing that farm productivity is not as great as it might have been is a clever rhetorical trick. In reality, agricultural output has been rising hell for leather since 1961.

The production of maize and wheat is up by over 200%. Rice and soybeans are up about 150%. Barley is up over 100%, and bananas, peas, beans, potatoes, cocoa beans and cassava are all up between 50% and 100%.

In all the above cases, the productivity growth rate has not slowed down, despite a modest rise in average global temperatures over the almost 60-year period.

So, what did the ‘research’ involve, then? First, they try to determine total factor productivity for agriculture around the world. This is supposed to measure total output in crops or livestock as a function of inputs such as labour, land, capital and materials.

Then they create a complicated formula relating observed and unobserved inputs, technological knowledge, and the effect of the weather to aggregate output.

The authors leave unexplained how they determine ‘unobserved’ inputs, or even what they are. They don’t explain why the effect of weather is the only factor represented by an exponential function. They don’t explain how they calculate the ‘technological knowledge’ factor, either.

They then construct a quadratic formula to calculate the actual effect of weather as a function of temperature and rainfall. Why a quadratic, is anyone’s guess. It’s all pretty opaque to the lay mind.

A complex econometric model is constructed in this manner, covering 172 different countries. These are then linked to numerous counterfactual climate scenarios using a popular ensemble of climate models. Climate models are themselves notorious for their complexity.

Somehow, out of all this complexity, drops a precise number: 20.8%, which represents how much lower agricultural output is in reality than it might have been had human-induced climate change not intervened.

The problem with complexity is that it can lead to what modellers call an ‘uncertainty cascade’. That is when additional complexity can make a model conceptually more complete, while making its predictions less and less useful.

Yet more uncertainty

The number of constants and coefficients that need to be estimated to achieve the paper’s results suggests the final number is no better than an educated guess. Coupling uncertainty with uncertainty produces yet more uncertainty, but that did not deter our brave modellers, who undoubtedly knew exactly what result they wanted.

The paper worries that the speculative impacts of climate change appear to fall most heavily upon sub-Saharan Africa. Yet it makes no effort to address the fact that fertiliser use in sub-Saharan Africa is less than 10% of the global average, leaving its cereal crop yield at 25% of what it could be. This could easily explain all the effects the paper attributes instead to the weather.

The massive headroom in yields in Africa also certainly suggests that even if climate change has a small negative impact on agricultural productivity, this can easily be counteracted by improved farming methods.

The paper doesn’t explain why climate change would have a negative impact on agriculture in the first place, however.

Higher levels of carbon dioxide in the atmosphere boost crop yields and improve the water-use efficiency of plants. The paper itself shows no significant changes in precipitation, and there is not much of a trend in droughts globally, either. It is unclear, therefore, by what mechanism a half-degree temperature rise might adversely affect farm productivity.

Overall, the approach taken in the paper looks a lot like self-gratification for data junkies and statistics nerds. It has so many variables that it could be tuned to produce just about any result you want, and as such, it cannot tell us anything useful about the world.

Risen inexorably

The Guardian does not feel we should celebrate that we’re still comfortably able to feed the growing world population, or that we need only 30% of the land we needed in 1961 to produce the same amount of crops, or that the total area of Earth’s surface dedicated to farming has reached its peak, or that the share of people that are undernourished in developing countries was three times as high in the 1960s as it is today, or that per capita calorie intake has risen inexorably since 1961, both globally and in Africa, or that Africa lags the rest of the world by only two decades in this regard.

No, we need to fret over the fact that in a changing climate (sorry, emergency!!!), we face continuing population growth and the need to feed more people. We should ignore that the global population growth rate peaked at 2.2% in 1962/3, has halved since then, and will approach zero by the end of the century.

We should ignore that there is no indication in the real-world statistics (as opposed to their craftily constructed computer models) that agricultural productivity is facing an imminent reversal from its long-term trend.

And we should definitely ignore the fact that poverty and hunger, far from being associated with climate change (excuse me, the climate panic!), is strongly associated with socialism, corruption, poor governance and conflict.

That would be a micro-aggression against The Guardian’s eco-socialist dreams, and we simply could not tolerate that.

https://dailyfriend.co.za/2021/04/27/is-farm-productivity-already-declining-due-to-climate-change/

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