Using producers’ own production and financial data from the Goulburn region, modelling was initially undertaken to assess pasture and livestock production, and enterprise profitability for two prior periods (1970-1999 and 2000-2009) to ensure the models were performing correctly. Modelling was then performed looking ahead to 2030, using 4 different climate scenarios. Two enterprises were examined – a self-replacing 18 micron merino sheep enterprise and a self- replacing beef cattle herd for feeder steer production
The enterprises modelled were based on a phalaris and sub-clover pasture with average fertility
Weather predictions & pasture production
Projected weather for the four 2030 scenarios and the impact on pasture production are shown below
- Compared to 1970-1999, over the period 2000-2009 rainfall was 19% lower, average maximum temperature was 4% higher and pasture production 21% lower
- For 2030:
- The temperature increases are consistent across the four scenarios but the rainfall forecast is variable from a 3% to a 20% decrease (average 10% decrease).
- This leads, on average, to a decrease (7%) in annual pasture production.
- To maintain minimum ground cover, a decrease in stocking rate is required, even for the model which had higher annual pasture production. The lower stocking rate reduces profits significantly (see 10.007)
- Winter pasture production is increased but autumn and spring drops.
Livestock & Financial Impacts, and Adaptations
Using the modeled pasture production figures, the impacts on livestock production and farm profitability were then calculated. Such impacts were initially based on a “business as usual” case i.e. no adaptations (changes to farm management practices) were made.
Then, by discussing these predicted results with farmers, a series of possible adaptations were agreed to and modeled. These adaptations were assessed for their ability (either individually or in combination) to help reduce the impact of climate change on livestock production and farm profitability.
To see the ‘business as usual’ impacts, and then what adaptations were proposed by producers and modeled, for both a sheep and beef enterprises at Goulburn, please click on: