Reducing emissions could mitigate worst effects of climate change, study finds

The worst effects of climate change could be mitigated by reducing greenhouse gas emissions, according to a study.

An international team of scientists, including researchers from the University of Leeds, used 20 different climate models around the world to examine how rainfall could be impacted by climate change.

The team then combined the models with reduced greenhouse gas emission scenarios to predict how the areas might be affected.

Their study, published in the journal Proceedings of the National Academy of Sciences, warns that up to 14% of land dedicated to wheat, maize, rice and soybean could have less rainfall, while up to 31% may see increases in rainfall.

Under a high emission scenario, France, Australia and Turkey, three of the world’s top 15 wheat producers, would see 26%, 28% and 88% of their land affected by reduced rainfall. In France and Turkey this is reduced to 0% under the lowest emission scenario, and in Australia it reduces to 4%.

China and India are the world’s two biggest rice producers and are among the countries predicted to have wetter conditions for all four crops included in the study, even in a scenario with low levels of emissions.

However, curtailing greenhouse gas emissions from high to low levels reduces the area affected from 11% down to 6% for China, and 80% to 17% for India.

The study warns that without significant reductions in greenhouse gas emission, patterns of increased precipitation in high latitudes, including areas in North America and Europe could emerge as early as the 2020s, and in some areas may have already altered due to climate change.

Study co-author Professor Challinor, from the Priestley International Centre for Climate at Leeds, said: ‘Changes in rainfall patterns have been challenging to predict in the past, making it difficult to offer advice on how growing conditions may change. This is the first study to overlay predicted time of emergence on croplands and growing seasons.

‘Wheat, maize, rice and soybean represent roughly 40% of global caloric intake and our findings show that by limiting greenhouse gas emissions we can help preserve the rainfall patterns vital for their growth.

‘While low-emissions scenarios still showed some effect on rainfall patterns in certain regions, the higher the amount of greenhouse gas emissions, the higher the percentage of land affected by drier conditions in key crop growing areas, such as South Western Australia and Southern Africa.

‘The greenhouse gas mitigation measures needed to achieve climate targets, such as the one set by the Paris Agreement, will go a long way to helping us reduce the risk of future droughts or flood conditions and possibly avoid a global food crisis.’

A study from August warned that global food production may be under threat from the impact of ozone air pollution on crop yields.

It looked at the impact of the pollutant on four staple crops in growing regions across the world: soybean, wheat, rice and maize, researchers estimated that ozone may reduce yields by up to 227 million tonnes a year.