Use your social profile entry

Global warming could cut essential crop harvests in half

Production of some of the most important food crops – wheat, soybean and maize – could be reduced by up to 50 per cent by the end of the century as the world gets warmer, a new study has found.

Researchers developed a computer simulation of how crops responded to rising temperatures, then tested this against real-world examples.

They found they could accurately predict how various different plants would respond.

And their findings were stark.

Without significant reductions in emissions, maize yields in the US could fall by nearly 50 per cent by 2100.

And soybean crops could see a 40 per cent reduction, while a 20 per cent reduction in wheat was also possible.

The US is one of the world’s largest exporters of crops. A dramatic cut in yields would have a serious effect on food prices around the world, causing food shortages in the poorest countries.

This could increase migration as people go in search of food and create conflict and, potentially, full-blown wars.

Bernhard Schauberger, of the Potsdam Institute for Climate Impact Research, who led the study by an international team of scientists, said: “We know from observations that high temperatures can harm crops, but now we have a much better understanding of the processes.

“The computer simulations that we do are based on robust knowledge from physics, chemistry, biology; on a lot of data and elaborate algorithms.

“But they of course cannot represent the entire complexity of the crop system, hence we call them models.

“In our study, they have passed a critical test.”

However the researchers said that farmers could off-set the losses by increasing irrigation – if there was enough water available.

“The losses got substantially reduced when we increased irrigation of fields in the simulation, so water stress resulting from temperature increase seems to be a bigger factor than the heat itself,” said researcher Joshua Elliott, of Chicago University.

“Irrigation therefore could be an important means of adaptation to dampen the most severe effects of warming.

“However, this is of course limited by the lack of water resources in some regions.”