Using producers’ own production and financial data from the Keith region, modelling was initially undertaken to assess pasture and livestock production, and enterprise profitability for two prior periods (1970-1999 and 2000-2008) to ensure the models were performing correctly. Modelling was then performed looking ahead to 2030, using 4 different climate scenarios.
Two enterprises were examined:
- Angus Cows. Soil type: Loamy Sand over Sandy Clay Loam. Pasture: Annual Grass, Capeweed and Lucerne; and
- Self-replacing wool Merino’s. Soil type: Loamy Sand over Deep Bleached Sand. Pasture: Lucerne, Annual Grass and Capeweed.
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 2000-2008 rainfall was 16% lower, average maximum temperature 5% higher and pasture production about 35% lower
- For 2030:
- The temperature increases are consistent (+5%) but the rainfall forecast is slightly more variable ranging from a -3% to – 16%, and averaging a 10% reduction.
- On average, there is a 13% to 16% decrease in annual pasture production (range -7% to -28%)
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 the two enterprises at Keith, please click on: