SSP Symposium ‚Climate Change‘, Zurich, 12 September 08
Climate change and
agriculture
Jürg Fuhrer
Air Pollution/Climate Group, Agroscope ART, Zurich
Climate change and agriculture
EU Green Paper: Adapting to climate change in Europe –
Options for EU actions, June 2007
”European agriculture will face many challenges over the
coming years:
International competition
Further liberalization of trade policy
Population decline
Climate change will add to these pressures and will
make the challenges more difficult and costly.
Under a changing climate, the role of EU agriculture and
forestry as providers of environmental and ecosystem
services will further gain importance.”
© agroscope ART – J Fuhrer
Climate change and agriculture
Changes in climate factors
(atmospheric CO2, temperature, precipitation, solar
radiation,…) affect agricultural
systems in multiple ways
They affect photosynthesis,
vegetative development, crop
yield and quality, and cropwater relations, as well as
insect pests, diseases and
weeds
Effects occur in combination
and at all levels of complexity
(plot, farm,..)
Climate system
Crop(s)
Crop
Crop
Crop
Pasture
Cropping system(s)
Livestock
Livestock system
Farming system
Socio-economic system
© agroscope ART – J Fuhrer
Crop yield: CO2 x Temperature
2.0
Summary of experimental results
1.6
1.4
1.2
1.0
0.8
0.6
0.4
+ 1-4 oC
0.2
0.0
CO 2
Temp
CO 2 +Temp
© agroscope ART – J Fuhrer
Amthor J, 2001; Fuhrer J, 2003
Relative yield change
1.8
Global climate projections
Winter
IPCC, 2007
Summer
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Changes in land suitability
2080s
© agroscope ART – J Fuhrer
Fischer G et al., 2005
1961-1990
Changes in crop production potential
Multiple cropping of rainfed cereals
ECHAM4/2080
%
Fischer G et al., 2001
-
+
© agroscope ART – J Fuhrer
Growth-limiting climatic factors
Temperature limitation: physiology and growing season length
ΔT
ΔT
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IPCC, 2007
Sensitivity of cereal yield
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Impacts in food-insecure regions
Lobell et al., 2008
(2030 in % of 1998-2002 yields, climate projections from 20 GCMs)
© agroscope ART – J Fuhrer
Impact on agricultural productivity
Based on agricultural impact models (”Ricardian” statistical economic
models and process-based agronomic crop models), combined with
IPCC climate projections. Cline, W. (2007)
© agroscope ART – J Fuhrer
Projections for Europe - Precipitation
Simulated changes in winter
(DJF) and summer (JJA)
precipitation from the period
1961-1990 to 2071-2100.
Left: boundary conditions from the
Hadley Centre
Right: boundary conditions from the
Max-Planck Institute for Meteorology
(source: PRUDENCE).
Warm and dry summers in the
south, mild and wet winters in
the north.
© agroscope ART – J Fuhrer
Crop yield potential changes (%)
ECHAM4/RCA3 A2 scenario
EU Green Paper 2007
HADCM3/HIRHAM A2 scenario
© agroscope ART – J Fuhrer
Projections for Switzerland
North of the Alps
[ΔoC]
Temperature
Precipitation
[Rc/Rs]
OcCC 2005: Die Klimazukunft der Schweiz - Eine probabilistische Projektion (Autor: Christoph Frei). In "Die Schweiz im
Jahr 2050".
© agroscope ART – J Fuhrer
Simulated pasture yield (PaSim)
2070-2100
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Winners and Loosers?
Yield deviation from national mean 1988-2007
Climate projetion based on OcCC scenarios (mean changes)
Sugarbeet
Current
Mean temperature in July (oC)
Precipitation in July (mm)
Precipitation in July (mm)
Potato
Mean temperature in June (oC)
© agroscope ART – J Fuhrer
Simulated crop yield (CropSyst)
10
Maize
Wheat
Maize
Oilseed rape
Wheat
Canola
Yield [t ha-1]
8
6
0.094
0.112
4
0.140
0.180
0.152
0.177
0.263 0.149
0.094
0.120
0.151
2
0.219 0.153
0.104
0.144
0
Baseline
CC- CM-
CC+ CM+ Baseline
CC- CM-
CC+ CM+ Baseline
CC- CM-
CC+ CM+
Baseline: 1981-2003
CC: Scenario 2071-2100, HIRHAM4 (A2), without (-) or with (+) CO2
effect
CM: Changes in means; CC: Changes in means and variability
(Numbers are CV)
Torriani D. et al., 2007
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Production risk
Grain maize in
Switzerland
Current climate
(Baseline)
-1
Crop yield (t ha )
Coefficient of variation = Measure for yield stability
© agroscope ART – J Fuhrer
After Torriani D. et.al. 2007
Frequency (%)
Profit ≤ 0
Critical yield
Local production risk
Grain maize in
Switzerland
After Torriani D. et.al. 2007
Critical yield
Without adaptation: risk increases from 28% to 80%
© agroscope ART – J Fuhrer
The effect of adaptation
Körnermais
Tänikon
12
10
8
6
4
Today
+ 0.8 +2.2
+5 oC
0
1980
2000
2020
2040
2060
2080
2100
© agroscope ART – J Fuhrer
Data from S. Schmid (unpubl.)
and Torriani D. et al. 2007
With adaptation
Shifting plant development
Calanca PL ART
Pattern of temperature sum, GDD, 1961-1990 (black),
and according to OcCC scenarios for 2050
Start of growing period
(GDD = 0 C d)
Time of anthesis for
cetreals (GDD = 2000
oC d, basis =0 oC)
Day of year
Crops: Shift of key phenological stages by 4 days oC-1
Estrella N. et al., GCB 2007 (for Germany)
© agroscope ART – J Fuhrer
Adjusting thermal requirements
Simulation with CropSyst using CC scenario from HIRHAM4
Change in thermal time requirement (growing degree-days,
GDD in oC-d)
Maize
Winter wheat
Oilseed rape
16
14
Maize
Winter wheat
Winter canola
10
8
0.098
0.117
6
4
2
0.183
0.189
0.177
0.183
0.098
0.094
0.115
0.263
0.342
0.103
0
CC+ -10% +20% +40%
GDD
CC+ -10% +20% +40%
GDD
CC+ -10% +20% +40%
GDD
© agroscope ART – J Fuhrer
Torriani D. et al., 2007
Yield [t ha-1]
12
Climate risks
Drought (lack of available soil moisture)
Heat (>35 °C), in combination with dry air and
intense solar radiation
Flooding (anoxia in the soil, soil erosion) and storms
Cold weather/Frost
Hail
Different scales!
© agroscope ART – J Fuhrer
US Global Change Research Program, 2000
Extremes and yield
© agroscope ART – J Fuhrer
Drought worldwide (IPCC A1B)
Change in 30-yr mean of
maximum drought
periods (length) in 20712100 relative to mean in
1961-1990.
(MPI Hamburg, 2006)
%
Different climate models project different worldwide changes in net
irrigation requirements, with estimated increases ranging from 1–3%
by the 2020s and 2–7% by the 2070s.
© agroscope ART – J Fuhrer
Increasing drought risk in Switzerland
Swiss Central Plateau, sandy loam soil, 30-yr Period
OcCC Scenario: +2 oC temperature, -20% precipitation
Critical soil moisture
content
Calanca, P.L. 2006
Scenario: 40%
Current: 15%
Normalized soil moisture
© agroscope ART – J Fuhrer
Water availability and consumption
(Thur catchment)
Reference (1981-2000)
25
Scenario range (2081-2100)
(%)
20
15
2003
10
(mm/10 Days)
05
Water
consumption
50% usable field
capacity
30%
J
F
M
A
M
J
J
2003: Representative of
an extrem year
Thur
A
S
O
N
D
O
N
D
Jasper K. et al. 2004
Soil water content
30
New
Maize
J
F
M
A
M
J
J
A
S
© agroscope ART – J Fuhrer
Temperature: Mean and variability
2003
Observation
Schär C. et al., 2004
Climate model
26.09.2008/Seite 28
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More hot days during summer
14
12
T>35°C
10
8
6
4
2
0
Observation
1961-1991
Model
1961-1991
Model
2071-2100
© agroscope ART – J Fuhrer
M. Beniston, Univ. Genève (PRUDENCE)
Number of days per year
Number of days with T > 35 °C at Basel, CH (A2)
http://www.rdg.ac.uk/pel/cropsandclimate/CCG-poster.pdf
Temperature thresholds
o
>30-32
>30-32 oCCat
atanthesis
anthesisinduces
induces
anther
anthersterility
sterilityininwheat
wheatand
andrice
rice
o
(5%-decrease
(5%-decreaseininyield
yieldfor
foreach
each oCC
o
increase
increaseabove
above32
32 oC)
C)
o
Temperatures
Temperatures>32-35
>32-35 oCCcauses
causes
bolls
bollsto
toabort
abortininpeanut,
peanut,and
and>40
>40
oo
CCinincotton.
cotton.
Reproductive limits for most crops are narrow, with temperatures in
the mid 30oC representing the threshold for successful grain set.
(Porter JR and Semonov MA, 2005)
© agroscope ART – J Fuhrer
Livestock: Heat stress
Thermal heat index calculated
from temperature and humidity
80
Wynau
21 days
Thermal Heat Index
70
Critical value
0 days
60
Conditions leading to heat
stress (like in 2003) are
becoming more frequent.
This leads to declining
animal productivity and
health.
50
40
2003
2007
30
20
0
50
100
150
200
250
300
350
Day of Year
Fuhrer J, ART
© agroscope ART – J Fuhrer
Additional threats
Puccinia graminis
Spread of diseases
e.g. black stem rust, caused by
the fungus Puccinia graminis
Mycus persicae
Increased pest infestations
e.g. aphids
Increased weed pressure
e.g. Cirsium arvense, Chenopodium
spp., Abutilon theophrasti
© agroscope ART – J Fuhrer
Adaptation and risk management
On-Farm Instruments
Market-based (RiskSharing) Instruments
Risk prevention
• Changing farm operation
• Changing land use and soil
management, plant protection
• Switching crop type/cropping
sequence, intercropping
• Irrigation
• Use of seasonal forecasts
Risk pooling
(insurance)
Risk transfer
via contracting
(‚Weather market‘)
Diversification
• Production
• Income
Holding reserves
© agroscope ART – J Fuhrer
Berg E., Schmitz, B., EAAE 2007 (modified)
Risk management instruments
Summary
Climate change will affect all aspects of
agricultural production, with strong regional
differences in magnitude and/or direction
Changing water availability will be crucial
Lower latitudes are most at risk from declining
productivity and decreasing food security
Increasing risks associated with extremes
(drought, heat, flooding,…) are most relevant
for both plant and animal production
Measures to adapt and to better manage
climate risks are necessary
© agroscope ART – J Fuhrer
Thank you for your attention!
©agroscope
agroscopeART
ART––J JFuhrer
Fuhrer
Baseline 1961–1990
a
Estimated yield (t ha-1) for the
baseline (a) and qualitative
changes for 9 RCMs with
HadAM3H as bounding GCM (b)
A2 Scenario 2071-2100
b
Diverging results
Increases in all model runs
Decreases in all model runs
Grey areas are estimated to be
unsuitable for winter wheat.
© agroscope ART – J Fuhrer
Olesen et al., Climatic Change 2007 (PRUDENCE)
Regional impacts – wheat yield