News › Scientists identify shortcomings in UK government's Climate Change Risk Assessment

Harvesting wheat

11 April 2012

Scientists at Rothamsted Research have described wheat yield predictions in the UK Climate Change Risk Assessment (CCRA) as "seriously misleading" in a letter published in Nature Climate Change today.

CCRA was commissioned by the Department for Environment, Food and Rural Affairs (Defra) and published in the UK on 25 January 2012. It makes a number of predictions but one of them, a prediction of a 40–140% increase in wheat yield by 2050 due to global warming, is based on a simplistic approach that ignores key factors affecting yields.

The lead author, Dr Mikhail Semenov said "the approach used by the report did not take account of the major factors that have been responsible for the increased wheat yields over the past 50 years". He added, "the predicted increases in yield in this report are therefore seriously misleading".

Rothamsted Research, which receives strategic funding from the BBSRC, has considerable expertise in the science behind wheat having run long-term wheat experiments continuously for 168 years. Using this knowledge, data and their world-renowned expertise in mathematical modelling they have predicted that increases in temperature alone will result in a decrease in wheat yield, which is in direct contrast to the CCRA report. Dr Semenov argues that "there is no doubt that the average UK wheat yield has doubled since the 1960s, however this increase in yield has resulted from a combination of several factors, notably genetic improvement resulting in high-yielding varieties, better management of pest and diseases and higher applications of fertiliser. He added "the assignment of this increase in yield solely to variation or changes in the mean temperature, as stated in the CCRA report, is therefore not correct and not supported by other studies."

The misleading wheat yield predictions in the CCRA report could have significant ramifications for the UK economy with wheat being the most important UK crop and a scientific priority area for UK Government, for example the BBSRC is funding a new exciting programme at Rothamsted Research to improve wheat yield to 20 tonnes per hectare in 20 years, called 20:20 Wheat®. Current average UK wheat yields are about 9 tonnes per hectare.

Rothamsted Research Press Office

For further information, please contact Darren Hughes, Head of Communications, on +44 (0) 1582 763 133 ext 2673, email darren.hughes@rothamsted.ac.uk

Rothamsted is the longest running agricultural research station in the world, providing cutting-edge science and innovation for nearly 170 years. Our mission is to deliver the knowledge and new practices to increase crop productivity and quality and to develop environmentally sustainable solutions for food and energy production. Our strength lies in our integrated, multidisciplinary approach to research in plant and soil science.

Rothamsted Research receives strategic funding from the Biotechnology and Biological Sciences Research Council (BBSRC) . It is the longest running agricultural research station in the world, developing environmentally sustainable solutions for food and energy production through science and innovation for nearly 170 years.

About BBSRC

BBSRC is the UK funding agency for research in the life sciences and the largest single public funder of agriculture and food-related research.

Sponsored by Government, BBSRC's budget for 2011-12 is around £445M which it is investing in a wide range of research that makes a significant contribution to the quality of life in the UK and beyond and supports a number of important industrial stakeholders, including the agriculture, food, chemical, healthcare and pharmaceutical sectors.

BBSRC provides institute strategic research grants to the following:

The Babraham Institute, Institute for Animal Health, Institute for Biological, Environmental and Rural Sciences (Aberystwyth University), Institute of Food Research, John Innes Centre, The Genome Analysis Centre, The Roslin Institute (University of Edinburgh) and Rothamsted Research.

The Institutes conduct long-term, mission-oriented research using specialist facilities. They have strong interactions with industry, Government departments and other end-users of their research.

For more information see: www.bbsrc.ac.uk