Wheat Yields To Fall (As They Continue To Rise)!

By Paul Homewood

 

Silly season continues at the BBC:

 

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Insects will be at the heart of worldwide crop losses as the climate warms up, predicts a US study.

Scientists estimate the pests will be eating 10-25% more wheat, rice and maize across the globe for each one degree rise in climate temperature.

Warming drives insect energy use and prompts them to eat more. Their populations can also increase.

This is bound to put pressure on the world’s leading cereal crops, says study co-author Curtis Deutsch.

"Insect pests currently consume the equivalent of one out of every 12 loaves of bread (before they ever get made). By the end of this century, if climate change continues unabated, insects will be eating more than two loaves of every 12 that could have been made," the University of Washington, US, researcher told BBC News.

Prof Deutsch, Joshua Tewksbury and colleagues have conducted a study on a global scale and looked at three different grain crops that are staple foods for billions of people.

The study, in the journal Science, uses data from across the globe to make a mathematical prediction that links the response of insects to temperature with the damage that is done to crops when the climate warms up.

Guy Poppy, who is Professor of Ecology at University of Southampton, UK, and works on food security said: "It is a novel piecing together of several pieces of a jigsaw".

The team put laboratory data from 38 insect species into the mathematical model. They looked to see how the energy use and growth responses of these insects to temperature might affect future crop losses.

There is already reckoned to be a direct effect of climate change on crops, with yields declining by about 5% for every one degree increase in temperature.

That loss will be 50% higher because of insect damage, said Prof Tewksbury from the University of Colorado Boulder, US.

So, this new research suggests the action of pests will accelerate temperature-induced impacts.

Which regions would be affected?

As the temperature rises insect populations grow and they eat faster. Prof Tewksbury added: "All of that adds up to bigger eating machines particularly in the temperate zone, like in the bread basket of Europe or in the corn belts of the US.

"In many European countries we’re predicting 50-100 % increases in the impact of pests on crops."

This could mean total losses in European wheat yield of around 16 million tons due to pests.

But in the tropics, insects are already closer to the optimal working temperature and a rise in temperature is actually likely to start limiting populations.

This would lead to fewer insects and fewer crops being damaged.

How will things play out?

Some of the world’s most productive regions of grain production are in the temperate zone and at risk, including US, France and China.

https://www.bbc.co.uk/news/science-environment-45358643

 

 

Meanwhile back in the real world:

 

 

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http://www.fao.org/faostat/en/#compare

via NOT A LOT OF PEOPLE KNOW THAT

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October 2, 2018 at 08:54AM

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