Risk matrix approach useful in adapting agriculture to climate change

A risk management approach to assessing climate change impacts was completed for grazing, wheat and sorghum production systems in eastern Australia. This ‘risk matrix’ approach for wheat and sorghum was compared to results from simulation modelling of the impacts of projected climate change from general circulation models (GCM’s). In the modelling we used five GCM’s, the A1FI emissions scenario and a baseline climate (historical, 1960–2010); both the ‘risk matrix’ approach and modelling used a time horizon of 2030. While some people find the risk matrix process a highly effective tool for assessing climate change impacts others question its utility without the support of quantitative data such as that produced from integrated climate and agricultural models. Here we show the impacts of climate change on wheat and sorghum production systems using both approaches, and also show the risk, adaptation responses and vulnerability of all three production systems using the ‘risk matrix’ approach. Advantages and disadvantages of each approach are identified. The independent assessment showed the two approaches produced similar results. The ‘risk matrix’ showed little overall impact, risk or vulnerability for the central slopes from climate change using the adaptation strategies currently available for yield, protein levels, pests and disease, weeds and soil condition. The simulation modelling showed no statistically significant impact on yield, drainage, erosion and runoff, although more high-end extremes were evident. The risks to 2030 from anthropogenic climate change can largely be managed by continuing to implement best management practice and managing the risks already posed by climate variability. The ‘risk matrix’ approach was a useful tool under these circumstances to assess the impacts, adaptation, risk and vulnerability of climate change in the absence of local modelling information, and demonstrates the power of expert opinion to help understand and respond to climate change at the regional scale.