The impact of projected climate change on Monaro farms. Doug Alcock Livestock Officer (Sheep and Wool) Climate Change Adaptation in Southern Australian Livestock Industries Project
Southern Livestock Adaptation 2030 National Project Uses modelling of –Climate –Pasture / Livestock Systems Compares current systems (1971 – 2000) with the same system in a projected climate (2030) Looking for adaptations to reduce impacts
What is a Global Climate Model? Global climate models (GCMs) combine knowledge of Physics, Fluid Dynamics and Chemistry to describe how –atmosphere, –oceans, –Land –Volcanic activity –living things –ice –Solar energy affect each other and Earth's climate.
What is a Global Climate Model? Equations are iterated on a 10 minute interval
Projections from 2000 Source IPCC IV How is has Temperature tracked since 2000?
Related trends?
Turning Global Scale Modelling into local projected weather! GCM,s operate as a broad brush. –Around 200km resolution Each cell gives a regional scale projection
Converting Climate to Weather Global Circulation Models Stochastic Weather Generator
Which emissions scenario? …Which GCM’s? CCSM 3.0 ECHAM5 OM GFDL 2.1 HadGEM1 Best GCM’s 2030
How can we assess the likely impact? Just as with projecting climate change modelling is the only way. One appropriate model is GrassGro
Weather / Climate Pasture Soil Livestock
How will plants respond to increased CO 2 Leaf Photosynthesis Leaf Water Loss Increased photosynthesis in C3 grasses and legumes (growth) Reduced water use Lower crude protein in grasses (higher CO 2 availability dilutes Nitrogen)
Climate Change at Bungarby
Base Farm System Merino Ewes 2.5 ewes/ha Nov Shorn Unfertilised native pasture on Stony Basalt. –Poa, Stipa, legume, annual grass. Sell progeny at 14 months Feed to maintain CS 2.
Bungarby’s weather data past and 2030 Annual RainfallAnnual Max / Min temperature 1971 to mm18.3 C / 4.8 C 2000 to mm19.1 C / 4.8 C CCSM (USA)605 mm (+11%)19.5 C / 5.9 C HadGEM1 (UK)561 mm (+3%)19.1 C / 5.7 C ECHAM5-OM (German)439 mm (-19%)19.7 C / 5.7 C GFDL 2.1 (USA)488 mm (-10%)19.5 C / 5.9 C
Bungarby projected 2030 rainfall compared to CCSM 3.0 HadGEM1 ECHAM5-OM GFDL
CCSM 3.0 HadGEM1ECHAM5-OM GFDL 2.1 Monthly Ave. Temp compared to “ ” Temperature °C
Bungarby projected pasture growth rate CCSM 3.0 HadGEM1 ECHAM5-OM GFDL
SUSTAINABILITY - EROSION Source: FERTILISER: A key to Profitable Livestock Production & Sustainable Pastures SOILLOSS software - DLWC
CCSM 3.0 HadGEM1ECHAM5-OM GFDL Annual Minimum Ground 2.5 ewes/ha Median Bottom 25% of years Top 25% of years Middle 50% of years
2.5 ewes/ha 13.8% of the time below 80% GC 70% of years Min GC > 80% 2.5 ewes/ha 30% of years Min GC > 80% 46.7% of the time below 80% GC 0.7 ewes/ha 63% of years Min GC > 80% 13.8% of the time below 80% GC
Merino breeding past and future Median Annual pasture kgDM/ha Sustainable Stocking Rate Average Profit/ha 1970 to ewes/ha$ to ewes/ha (1.5 ewes/ha) $52 ($8) CCSM ewes/ha$89 HadGEM ewes/ha$46 ECHAM5-OM ewes/ha-$31 GFDL ewes/ha$20
Projected profit for merino breeding at Bungarby CCSM 3.0 HadGEM1ECHAM5-OM GFDL /ha 2.5/ha
Annual Supplement (per ewe) CCSM 3.0 HadGEM1ECHAM5-OM GFDL
Annual supplement fed (per ha.) CCSM 3.0 HadGEM1ECHAM5-OM GFDL
Wool Cut CCSM 3.0 HadGEM1ECHAM5-OM GFDL
Condition Score at lambing CCSM 3.0 HadGEM1ECHAM5-OM GFDL
Reproduction CCSM 3.0 HadGEM1ECHAM5-OM GFDL
Ground Cover CCSM 3.0 HadGEM1ECHAM5-OM GFDL
Some other locations and enterprises Beef production near Nimmitabel –British Breed –Weaner Steer with heifers retained to yearling –Improved pasture (Fescue / Sub. Clover) –Fertilised deep duplex Granite soils Merino’s west of Bombala. –Self replacing merino flock –Cocksfoot/Sub with some cork-screw and annual grasses. –Fertilised deep loamy gradational soil (metasediment)
Projected Rainfall CCSM 3.0 HadGEM1ECHAM5-OM GFDL
Projected Pasture Growth at Nimmitabel CCSM 3.0 HadGEM1 ECHAM5-OM GFDL
Profit CCSM 3.0 HadGEM1ECHAM5-OM GFDL cows/ha 0.8 cows/ha 0.6 cows/ha 0.5 cows/ha 0.7 cows/ha
Some other locations and enterprises Merino’s west of Bombala. –Self replacing merino flock –Cocksfoot/Sub with some cork-screw and annual grasses. –Fertilised deep loamy soil
Projected rainfall near Bombala CCSM 3.0 HadGEM1ECHAM5-OM GFDL
Bombala projected pasture Growth CCSM 3.0 HadGEM1 ECHAM5-OM GFDL
Projected profit for merino ewes at Bombala CCSM 3.0 HadGEM1ECHAM5-OM GFDL ewes/ha 4.3 ewes/ha 3.1 ewes/ha 1.8 ewes/ha 2.1 ewes/ha
Possible impacts without adaptation Lower ground cover Lower sustainable carrying capacity Lower profits/ha. –BUT Not necessarily the case for all locations and all climate projections?
Possible Adaptations Drought lots (ground cover management) Genetic improvements Grazing management New species Enterprise changes Lambing / calving time
+ 10% Fleece -0.5 µm CCSM 3.0 HadGEM1ECHAM5-OM GFDL ewes/ha 4.3 ewes/ha 3.1 ewes/ha 1.8 ewes/ha 2.1 ewes/ha
Climate change is truly serious !
National Southern Livestock Adaptation 2030 Partners Local Cooperators