Transcript Is Australian agriculture the first casualty of

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 offfarm 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
Agricultural production is influenced by a
complex web of drivers
Energy usage
Demographic
change
Changing
lifestyles
Livestock
consumption
Climate
change
Desertification
Competing
land uses Degradation
Legislative
change
Sea levels
Agricultural
production
Ocean
chemistry
Freshwater
decline
Biodiversity
loss
Ecosystem
function
Resource
limitations
Globalisation &
commoditisation
Technology
change
Transport
costs
Political
change
Biofuels
Crop production driven by demand for food,
feed and fuel !
Crops used for
human consumption
Crops used
for Livestock
Crops used
for biofuels
• 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.
Crop yields have increased over time,
but……
4.0 8.0
3.5 7.0
Yield (t/ha)
Yield
Yield (t/ha)
3.0 6.0
Western
Europe
Asia
World
2.5 5.0
2.0 4.0
1.5 3.0
1.0 2.0
0.5 1.0
0.0 0.0
1955
19551960
1960 1965
1965 1970
1970 1975
1975 1980
1980 1985
1985 1990
1990 1995
1995 2000
2000 2005
2005
Year
Year
• 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.
2010
2010
Food security: yield growth rate
slowing
Yield
increase
(%)
Yield
increase
(%)
Yield
increase
(%)
5
5
Asia
Western
World
Europe
4
4
4
3
3
3
2
2
2
34%
15%
~0%
1
1
1
0
0
01950
1950
1950
1970
1970
1970
1990
1990
1990
Year
Year
Year
2010
2010
2010
2030
2030
2030
2050
2050
2050
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
Highly Effective Climate-risk
High Resolution Sectoral
sTrategies using Atmospheric
Applications Research
REconstructions
Historical impacts of climate on
production
• 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.
Source: Lobell and Field 2007
Australian warming accelerating
•
•
1957-2007
+0.19oC/decade
1975-2007
+0.22oC/decade
23
o
Temperature ( C)
24
1910-2007
•
+0.09oC/decade
22
21
20
1900
1920
1940
1960
1980
2000
Year
Source: CBoM
2020
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
Historical % change in stream flow)
• 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
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
Future global impacts on agriculture could
be significant
‘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)
National winners and losers
Some likelihood
of increased
summer rainfall
but temperature
will be a limiting
factor
Annual rainfall decline, strong
increases in inland
temperatures
Some likelihood
of increased
summer rainfall
temperature
slightly less of a
consideration
National: interaction with other drivers
•
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.
Howden et al. (2009)
Future wheat exports ? No adaptation
•
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
2000
Howden et al. (2009)
2020
2050
2070
Future wheat exports ? With
adaptation
•
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
Howden et al. (2009)
Future rangeland production
McKeon et al. (2009)
•
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.
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.
Source: Howden and Crimp 2005
Progressive adaptation
Benefit from
adaptation
Transformation from landuse or
distribution change
New products such as
ecosystem services
Climate ready germplasm
Climate-sensitive precision-agric
Diversification and risk management
Varieties, planting times, spacing
Stubble, water, nutrient and canopy
management etc
Climate change
Conclusions
HECTARE
ACRE
High Resolution Sectoral Applications Research
or
Highly Effective Climate-risk sTrategies using
Atmospheric REconstructions
•
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.
• 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]
Climate Adaptation Flagship
Steven Crimp
Phone: +61 2 6242 1679
Email: [email protected]
Website: www.csiro.au/org/ClimateAdaptationFlagship
Thank you