Is Australian agriculture the first casualty of global climate change?

Steven Crimp, Mark Howden, Greg McKeon,

Sarah Park and many others

CSIRO Sustainable Ecosystems

The human face of recent changes

• Samantha*, Simon* and their children have lived in a dust bowl for almost eight years. Limited and now zero water allocations have rendered their irrigated property in the Murray-Darling Basin dryland, making a mockery of harvests that historically yielded one tonne of wheat per acre .

• Simon’s taking anti-anxiety medication and contemplating seeking off-farm work, while Samantha juggles three part-time jobs with the care of their children and household.

• “My husband is a good farmer, an educated man, but he now questions every decision,” Samantha says.

• The couple’s agribusiness bank manager regretfully admits that they

are not alone. He says families in his region are “self-destructing because of the financial and personal pressures” – divorce rates are up, debt levels are crippling, and cashed-up operators are circling.

Outback Magazine – next addition

Resourcelimitations

Transportcosts

Legislative change

Biofuels

Livestockconsumption

Changinglifestyles

Demographicchange

Technologychange

Competing land uses

Politicalchange

Energy usage

Globalisation & commoditisation

Agricultural production is influenced by a complex web of drivers

Agricultural production

Climatechange

Sea levels

Oceanchemistry

Desertification

Degradation

Biodiversityloss

Ecosystemfunction

Freshwaterdecline

Crop production driven by demand for food, feed and fuel !

Crops used for biofuels

Crops used for Livestock

• Historically we can see that the demand for crops (coarse grains) have been as a result of interplay between human and livestock consumption and more recently biofuels.

• This interplay has changed and will continue to change over time.

• Biofuels is a relatively new player on the block, however in 3 years, biofuel use of grain increased by 47 million tonnes, amounting to approximately 60% of the increase in consumption.

Crops used for human consumption

0.0

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4.0

5.0

6.0

7.0

8.0

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Yie

ld (t

/ha)

Western Europe

Crop yields have increased over time, but……

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Yie

ld (t

/ha)

Asia

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Yie

ld (t

/ha)

World

• Over the last 48 years crop yields have more than doubled (1.2 t/ha to 3.3t/ha) in response to improved management, technology and genetics.

• A further doubling of current production levels by 2050 is required to match current growth in utilisation rates.

0

1

2

3

4

5

1950 1970 1990 2010 2030 2050

Year

Yie

ld in

cre

as

e (

%) Western

Europe

Food security: yield growth rate slowing

~0%0

1

2

3

4

5

1950 1970 1990 2010 2030 2050

Year

Yie

ld in

cre

as

e (

%) Asia

34%

0

1

2

3

4

5

1950 1970 1990 2010 2030 2050

Year

Yie

ld in

cre

as

e (

%)

World

15%

Rate of yield growth are slowing

• New Technologies, improved management and efficiencies will be required to maintain production growth at the required rate of 1.7% per year to double average production by 2050.

• Many of the data products from ACRE will provide important information on CV or CC and are thus components to inform the development of resilient production.

ACRE HECTARE

High Resolution Sectoral Applications Research

Highly Effective Climate-risk sTrategies using Atmospheric

REconstructions

• For wheat, maize and barley, there is a clearly negative response of global yields to increased temperatures.

• Since 1981 has resulted in annual combined losses of these three crops representing roughly 40 Mt or $5 billion per year, as of 2002.

Historical impacts of climate on production

Source: Lobell and Field 2007

20

21

22

23

24

1900 1920 1940 1960 1980 2000 2020

Year

Te

mp

era

ture

(o C)

Australian warming accelerating

• 1910-2007 +0.09oC/decade

Source: CBoM

• 1975-2007

+0.22oC/decade• 1957-2007

+0.19oC/decade

Emergence of changes in rainfall variability

• Change in rainfall variability between the 1900-1950 and 1950-2000.

Source: CBoM

Changes since 1991

McKeon et al 2009

Irrigated agriculture may be more at risk

• In regions where the historical climate trends match future projections some confidence exists in the direction and extent of future change.

• Projected declines in southern MDB flows (15 to 20% decline by 2030) may mean supporting current irrigated agriculture to move to more rainfed production.

• Regionalised policy intervention may be required.Source: ABARE, 2007 and CSIRO 2008

Historical % change in stream flow)

Industries in transition: Peanuts

• Warmer temperatures and declines in rainfall have already presented considerable challenges to peanut production.

• In response to these challenges PCA have recently invested roughly $200 million in developing new infrastructure in NT.

Source: PCA

‘Developing nations (A1FI): 42 developing countries may benefit from substantial increases in cereal-production potential averaging 17%. However, 52 countries with a population of up to 3 billion may lose on average 19% of their current yield potential by 2080.’

‘increase in cropland at higher latitudes (developed countries 160Mha) and a decline of cropland at lower latitudes (developing countries 110Mha) with a reduction in prime cropping land of 135Mha but an increase in moderately suitable land of 20Mha’

Fischer et al. (2005)

Future global impacts on agriculture could be significant

National winners and losers

Some likelihood of increased

summer rainfall temperature

slightly less of a

consideration

Some likelihood of increased

summer rainfall but temperature will be a limiting

factor

Annual rainfall decline, strong increases in inland

temperatures

• wheat is the major crop in Australia.

• production exceeds domestic consumption resulting in about 80% being exported averaging 15Mt p.a. – 12% of global trade.

• climate change (8 different models, A1FI scenario) interacting with increasing population and consumption patterns.

• Official ABS population statistics (Series A, B and C: ABS 2008).

• By 2070, high scenario (50M people); mid scenario (39M people); low scenario (33M people).

• Future per capita wheat consumption was assumed to be between 300 and 400kg per person per year and exports were calculated as the difference between production and consumption.

National: interaction with other drivers

Howden et al. (2009)

• with occurrence of worst case climate change, assuming no effective adaptation and high population change, Australia could become a net importer of wheat as soon as 2050

• at 2070 there is a 26% chance of Australia having no wheat surplus assuming no adaptation

• worst case being a net importer of 15Mt/year – about the same amount as is currently exported

Future wheat exports ? No adaptation

Howden et al. (2009)2000 2020 2050 2070

• practical adaptations reduce the chance of having no surplus to export to 10%.

• double the median surplus to 5Mt.

• preliminary study has used conservative assumptions in terms of both impacts and adaptation effectiveness. Nor has it included climate variability, ongoing yield improvements, landuse change or market-based feedbacks

Future wheat exports ? With adaptation

Howden et al. (2009)

Future rangeland production

• Pasture production modelling made possible using the AussieGRASS model.

• Based on median estimates of climate change across Australia pasture production is likely to vary little in the higher rainfall zones but decline by up to 20% on the drier margins.

McKeon et al. (2009)

Source: Howden and Crimp 2005

Understanding the value of adaptation

• Adaptations were most effective with small temperature increases (1 to 2oC), raising yields by 6 to 12%

• At higher temperatures, further benefits are limited, particularly under scenarios with reduced rainfall.

Progressive adaptation

Varieties, planting times, spacing

Stubble, water, nutrient and canopy management etc

Climate ready germplasm

Climate-sensitive precision-agric

Diversification and risk management

Transformation from landuse or distribution change

New products such as ecosystem services

Climate change

Ben

efit

fro

m

adap

tati

on

Incr

easi

ng c

ompl

exity

,

cost

and

risk

Conclusions

• The activities of ACRE could provide important insights:

• Into yield-limiting factors under climate change, achieving positive yield trends whilst reducing inputs and unwanted feedbacks

• New assessments of food security futures taking into account the constraining factors here and new climate change scenarios

• Focus on managing climate variability through more effective delivery of useful information higher resolutions.

ACRE HECTAREHigh Resolution Sectoral Applications Research

Highly Effective Climate-risk sTrategies using Atmospheric REconstructions

or

• The people of the pastoral country in Australia...think a lot of the weather. Or, to be more exact, they think a lot about it. Of the weather, and of the rain which doesn't come when it should, or comes too suddenly and too heavily, they have not a very high opinion.

[Francis Ratcliffe, Flying Fox and Drifting Sand, 1938]

Thank you

Climate Adaptation FlagshipSteven Crimp

Phone: +61 2 6242 1679Email: mark.howden@csiro.au

Website: www.csiro.au/org/ClimateAdaptationFlagship