The team at CSIRO Plant Industries, used the GRAZPLAN simulation models of pasture and livestock production to explore a variety of issues relating to livestock producers and climate change. The centrepiece of the research was an analysis of livestock production systems for all combinations of:
- 25 locations across southern Australia
- Representative of regions of equal Gross Value of Annual Production
- 5 livestock enterprises – Merino & crossbred ewes, wethers, breeding cows, steers
- Same weather + soils + pastures for each location
- Same costs & prices for each enterprise
- Projections for 2030, 2050, 2070 – GCM predictions of changes in rainfall variability in the “downscaled” weather inputs
- 4 Global Circulation Models of scenario A2 to capture the “uncertainty” of future climates
- 9 adaptive changes to management or genetics at different levels (singly and in combinations).
Despite the enormous complexity of the research (unlikely to have been attempted before worldwide for any agricultural industry) a set of key messages emerged from the mass of modelling results:
- In the absence of adaptation, the magnitude of climate change impacts will be large; the potential exists for a significant decrease in the total value of livestock production.
- Based on the available projections, there is a real prospect of 15-20% overall reductions in pasture growth by 2030 in the absence of adaptation. View more information.
- Declines in livestock production and profitability can be expected to be significantly larger than declines in total pasture growth. This difference is caused by the need to leave herbage unconsumed (i.e. groundcover) to protect the soil resource. An average 15% to 20% reduction in pasture production can lead to a 20 to 50% reduction in livestock production and profitability. View more information.
- Climate change impacts, and hence the need for adaptive responses, are greatest in the lower-rainfall parts of the cereal-livestock zone and tend to be less severe in the south-eastern parts of the high-rainfall zone.
- Taken across southern Australia, all broadacre livestock enterprises are likely to be strongly affected by projected future climates.
- The uncertainty associated with these projected changes in livestock production is large – and is caused by uncertainty in rainfall projections – but the above trends are discernable nonetheless.
- A range of different adaptations, based on currently-available technologies, are potentially effective in ameliorating the impacts of projected climate changes. The most important of these are:
- increasing soil fertility;
- ongoing genetic improvement of livestock;
- introduction or increased use of summer-active perennials (particularly lucerne);
- in some locations, the use of confinement feeding to protect ground cover.
- While at a few locations, a single adaptation can be effective, particularly for 2030, in general no single adaptation will fully ameliorate the challenges to the broadacre livestock industries from climate change. In most situations, a combination of adaptive responses will be required.
- It is likely that in 2030, combinations of adaptations can be found to return most livestock production systems to profitability. By 2050 and 2070, on the other hand, the findings suggest that the lower-rainfall parts of the cereal-livestock zone will require either new technologies, a complete re-thinking of the feedbase or else sustained price increases in order for livestock production to remain viable. View more information about the impacts of adaptations on reducing the effect of climate change.
An important conclusion is that there are changes to management – in particular management for increased soil fertility and the adoption of systematic genetic improvement of flocks and herds – that are (i) likely to be sound adaptations to changing climates, (ii) need to be carried out over the long term and (iii) are likely to be sound investments in the present-day climate. The case for these adaptations should therefore be made with renewed force.
Specific papers on elements of CSIRO’s research can be found in the following documents. Click on the one you wish to review:
- A review of prior work relating to adaptation of southern Australian livestock production to climate change
- Natural selection in southern Australian pastures under climate change: a brief review
- Effectiveness of a range of grazing system adaptations in ameliorating the impacts of shorter growing seasons
- Will managing for climate variability also manage for climate change? A southern Australian grazing system as an example
- Medium-term climatic variability and its effects on pasture and livestock production: consequences for projections of climate change impacts
- Impacts of climate change to 2070 at eight locations across southern New South Wales: a preliminary analysis
- Impacts of climate change across southern Australia in 2030, 2050 and 2070
- Adaptations to climate change across southern Australia in 2030, 2050 and 2070
- Testing the responses of the GRAZPLAN model to increased atmospheric CO2
- Improving and extending the parameter sets for the GRAZPLAN pasture model
- Characteristics of the locations, land resources and livestock production systems used in the GrassGro modelling of climate change impacts and adaptations
View more information on CSIRO’s climate change flagship.