The agricultural impacts on the map were generated from work from a variety of sources. These include the Intergovernmental Panel on Climate Change Working Group 2 report, Impacts, adaptation and vulnerability, 2007, research at the Met Office Hadley Centre and research done by the Walker Institute for Climate System Research, University of Reading.

 

The Met Office Hadley Centre produced a poster providing an overview of the impacts of climate change on agriculture for a range of temperatures (see below). This gives some background information on the subject.

 

In addition the IPCC WG2 report has collated a great deal of research about the impacts of climate change on agriculture, and this resource was used to support statements about maize, wheat and rice on the poster.

 

Finally, specific research was done by Prof. Tim Wheeler at the Walker Institute for Climate System Research, University of Reading, looking at the affect of an increase of global average temperature of +4 oC, on the productivity of soya bean crops.  A description of this research and some of the results used for the poster are given below

 

Soy bean Productivity

 

The productivity of crops is inherently sensitive to variability in climate. Altered temperature and rainfall patterns, and extreme weather events, under climate change will affect the harvested yield of food crops. One approach to studying the potential impacts of climate on crops is to use crop models to simulate crop growth, development and yield under different climate change scenarios. For a global study, for example, the results of such a study could be shown as a map of changes in yield from our current climate to a future one. This yield difference is the potential climate change signal for crops. It could also be viewed as a target for adaptation of crop production to climate change.

 

Figure 1 below shows the result of one such climate change impacts study for the world’s most important grain legume crop, soya bean. Here, we simulate the impacts of a +4 ºC warming scenario on the productivity (yield) of soya bean, expressed as a percentage change in productivity from the baseline climate.

 

Climate change patterns from the Met Office Hadley Centre QUMP 17-member ensemble were used to generate the +4 ºC future climate projection using pattern-scaling (Osborne et al., 2009 Walker Institute Report, Sept 2009). Crop productivity (yield, in t ha-1) was simulated for each climate ensemble using the GLAM crop model (Challinor et al., 2004 Ag For Met 124, 99-120) modified to represent 3 maturity groups of soya bean (G. Rose, pers comm.). Suitable areas for soya bean crop production in the future climate were defined using a crop mask (Osborne et al., 207, Global Change Biol 13, 169-183). The ensemble mean change is shown.

 

The results of this simulation show that yields of soya bean will decline in most parts of the world under the +4 ºC climate change scenario. A few regions show positive changes to yield, due to the use of different crop varieties, and so represent potential opportunities for adaptation to climate change. However, the general outlook for soya bean under this scenario of climate change is negative.

 

This information was combined with information on the distribution of soya bean crops in the present day (Monfreda et al., 2008), to highlight on the poster, the impact on areas soya bean is currently grown.

 

Figure 1.  Change of soya bean yield for a global average temperature rise of +4 ºC

 

References

 

Challinor A.J., Wheeler T.R., Craufurd P.Q., Slingo J.M. and Grimes D.I.F., 2004, Design and optimisation of a large-area process-based model for annual crops, Agricultural and Forest Meteorology, 124(1-2), 99-120.

 

Fischer, G., Shah, M. and van Velthuizen, H., 2002, Climate change and agricultural vulnerability, IIASA Special Report commissioned by the UN for the World Summit on Sustainable Development, Johannesburg 2002.  International Institute for Applied Systems Analysis, Laxenburg, Austria, 160 pp.  IPCC WG2

 

IPCC, 2007, Climate Change 2007: Impacts, Adaptation and Vulnerability, Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 976pp.  Pages 286, Fig 5.2 and p297, Fig. 5.3

 

Monfreda et al (2008) Geographical distribution of crop areas and yields, physiological types, and net primary production in the year 2000.  Global biogeochemical cycles Vol 22.  GB 1022.

 

Parry M. L., Rosenzweig C., Iglesias A., Livermore M., Fischer G., 2004, Effects of climate change on global food production under SRES emissions and socio-economic scenarios, Global Environmental Change, 14(1),  53-67

 

Osborne T.O, Lawrence D.M., Challinor A.J., Slingo J.M, Wheeler T.R., 2007. Development and assessment of a coupled crop-climate model, Global Change Biology, 13, 169-183.

 

2009 Walker Institute Report, Sept 2009

 

Related links

Impacts of Climate Change on Agriculture, PDF (287.12KB)