the impact of projected climate change on monaro farms. doug alcock livestock officer (sheep and...

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 C

irculation Models

Stochastic Weather Generator

Which emissions scenario? …Which GCM’s?

CCSM 3.0

ECHAM5 OMGFDL 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 CO2

Leaf Photosynthesis Leaf Water Loss

• Increased photosynthesis in C3 grasses and legumes (growth)• Reduced water use • Lower crude protein in grasses (higher CO2 availability dilutes Nitrogen)

Relative Assimilation Rate

0.90

0.95

1.00

1.05

1.10

1.15

1.20

350 400 450 500 550 600 650 700

C3 Grass, Legume

C4 Grass

Reference Stomatal Conductance (m/s)

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

350 400 450 500 550 600 650 700

C3 Grass

C4 Grass

Legume

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 Rainfall Annual Max / Min temperature

1971 to 2000 544 mm 18.3 C / 4.8 C

2000 to 2009 451 mm 19.1 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 1971-2000

CCSM 3.0 HadGEM1 ECHAM5-OM GFDL 2.11971-2000

CCSM 3.0 HadGEM1 ECHAM5-OM GFDL 2.1

-5

0

5

10

15

20

25

30

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Monthly Ave. Temp compared to “1971 -2000”T

empe

ratu

re °

C

Bungarby projected pasture growth rate


SUSTAINABILITY - EROSION

Source: FERTILISER: A key to Profitable Livestock Production & Sustainable Pastures

• SOILLOSS software - DLWC

CCSM 3.0 HadGEM1 ECHAM5-OM GFDL 2.11970 - 2000

Annual Minimum Ground Cover @ 2.5 ewes/ha

Median

Bottom 25% of years

Top 25% of years

Middle 50% of years

Baseline @ 2.5 ewes/ha

13.8% of the time below 80% GC

70% of years Min GC > 80%

Echam @ 2.5 ewes/ha



Echam @ 0.7 ewes/ha



Merino breeding past and future

Median Annual pasture kgDM/ha

Sustainable Stocking Rate

Average Profit/ha

1970 to 2000 5833 2.5 ewes/ha $72

2000 to 2009 4717 2.5 ewes/ha(1.5 ewes/ha)

$52($8)

CCSM 3.0 6697 2.6 ewes/ha $89

HadGEM1 6720 2 ewes/ha $46

ECHAM5-OM 4258 0.7 ewes/ha -$31

GFDL 5712 1.6 ewes/ha $20

Projected profit for merino breeding at Bungarby


2000

2001 2002

2003

2004

2005

2006

2007

20082009

1.5/

ha

2.5/

ha

Annual Supplement (per ewe)


Annual supplement fed (per ha.)


Wool Cut


Condition Score at lambing


Reproduction


Ground Cover


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


Projected Pasture Growth at Nimmitabel

0

10

20

30

40

50

60

70

80

1-Ja

n15

-Jan

29-J

an12

-Feb

26-F

eb12

-Mar

26-M

ar9-

Apr

23-A

pr7-

May

21-M

ay4-

Jun

18-J

un2-

Jul

16-J

ul30

-Jul

13-A

ug27

-Aug

10-S

ep24

-Sep

8-O

ct22

-Oct

5-N

ov19

-Nov

3-D

ec17

-Dec

Kg

Dry

Mat

ter/

ha/

day


Profit


0.6 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


Bombala projected pasture Growth

0

10

20

30

40

50

60

70

80

1-Ja

n15

-Jan

29-J

an12

-Feb

26-F

eb12

-Mar

26-M

ar9-

Apr

23-A

pr7-

May

21-M

ay4-

Jun

18-J

un2-

Jul

16-J

ul30

-Jul

13-A

ug27

-Aug

10-S

ep24

-Sep

8-O

ct22

-Oct

5-N

ov19

-Nov

3-D

ec17

-Dec

Kg

Dry

Mat

ter/

ha/

day


Projected profit for merino ewes at Bombala


4 ew

es/h

a

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 weight @ -0.5 µm


4 ew

es/h

a

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

the impact of projected climate change on monaro farms. doug alcock livestock officer (sheep and...

Documents

gc slide

bungarby slide

temperature c slide

nitrogen slide

grassgro slide

impacts slide

c gfdl

minute interval slide