The combination of rising temperatures and air
pollution could substantially damage crop growth in the next 40
years, according to a new paper. And if emissions stay as high as
they are now, the number of people who don't get enough food could
grow by half by the middle of the century.
Feeding the world's rapidly growing population is a
rising temperatures are likely to lead to lower crop
yields. Other work suggests air pollution might reduce the amount
of food produced worldwide. But nobody has considered both effects
together, say the paper's authors.
The two effects are closely related as
warmer temperatures increase the production of ozone in the
atmosphere, the paper explains.
new study looks at global yields of the four principle
food crops - wheat, rice, corn and soybean - and how they're
expected to change by 2050 under different levels of future
Together, these provide nearly
60 per cent of all the calories consumed by humans
The maps below show some of the results.
The top panel shows an optimistic scenario in which
greenhouse gases stabilise at 630 parts per million (ppm) by 2100.
For reference, we're at about 400 ppm now.
The team compared this with what might happen if greenhouse
gases continue to rise as rapidly as they are now. That's the