Climate change will reduce crop yield sooner than thought - researchers

A recent study by researchers at the University of Leeds, United Kingdom, has shown that global warming of only two degree Celsius will be detrimental to crops in temperate and tropical regions, with reduced yields from the 2030s onwards.

In the study published by the journal Nature Climate Change, the researchers created a new data set by combining and comparing results from 1,700 published assessments of the response that climate change will have on the yields of rice, maize and wheat.

Due to increased interest in climate change research, the new study was able to create the largest dataset to date on crop responses.

Professor Andy Challinor, from the School of Earth and Environment at the University of Leeds and lead author of the study, said: “Our research shows that crop yields will be negatively affected by climate change much earlier than expected.”

“Furthermore, the impact of climate change on crops will vary both from year-toyear and from place-to-place -- with the variability becoming greater as the weather becomes increasingly erratic.”

The researchers state that we will see, on average, an increasingly negative impact of climate change on crop yields from the 2030s onwards. The impact will be greatest in the second half of the century, when decreases of over 25% will become increasingly common.

From the research, later in the century, greater agricultural transformations and innovations will be needed in order to safeguard crop yields for future generations.

“Climate change means a less predictable harvest, with different countries winning and losing in different years. The overall picture remains negative, and we are now starting to see how research can support adaptation by avoiding the worse impacts,” concludes Professor Challinor.

Commenting on the study, Dr. Moses Adebayo of the Department of Crop Production and Soil Science, Ladoke Akintola University of Technology Ogbomoso, Oyo State, said several recent studies have expressed the same concern and he and some researchers (Adebayo et al 2014) have reported a maize yield reduction of over 70% due to severe drought this year.

He said a study by Reynolds and Ortiz in 2010 predicted that beginning from 2030; developing countries will be most adversely affected by climate change and another by Campos and others in 2004 expressed worry that with global climate change and its attendant rise in temperatures, significant yield losses will be expected in maize.

He said: “According to the Intergovernmental Panel on Climate Change (IPCC, 2009), rising temperatures, drought, floods, desertification and weather extremes are some of the indicators of climate change that will severely affect agriculture, particularly in the developing countries.”