Download 6 Climate impacts on sectors and policies

6
Climate impacts on sectors and policies
6.1
Agriculture
Notes:
 The document as it stands now is still largely a compilation of individual
contributions of JEO and AI. The introduction will include text linking the different
indicators.
 The current version includes some text from the 2008 report and the SOER that will
be modifies as the new conclusions and key messages are defined.
 Water limitation indicator will be further developed.
 Some internal comments are included to seek advice from the advisory group.
Comments welcome.
 All References are in Zotero group and zoterio citations will be included in this
document.
6.1.1
Introduction
The cultivation of crops, their productivity and quality, are directly dependant on different
climatic factors. Climate change is already having an impact on agriculture (Peltonen-Sainio
et al., 2010; Olesen et al., 2011), and has been attributed as one of the factors contributing to
yield stagnation in wheat in parts of Europe (Brisson et al., 2010). Measuring current and
future impacts of climate change on agriculture at the continental scale is a significant
challenge, but there is growing scientific consensus that climate-induced changes in
biodiversity and ecosystem services are occurring. Climate change is expected to continue to
affect agriculture in the future (J.E. Olesen et al. 2011; Ana Iglesias et al. 2010), and the
effects will vary greatly in space across Europe (M. Trnka, Olesen, et al. 2011; Ana Iglesias,
Garrote, Diz, Schlickenrieder, y Martin-Carrasco 2011a), but they may also change over time
(Miroslav Trnka, Eitzinger, et al. 2011). It is generally accepted that productivity will
increase in Northern Europe due to a lengthened growing season and an extension of the frost
free period (Olesen and Bindi, 2002; Trnka et al., 2011a; Iglesias et al., 2011b). In Southern
Europe, the impact of climate change on agriculture is likely to affect the productivity of
crops and their suitability in certain regions primarily due to extreme heat events and an
overall expected reduction in precipitation and water availability (Bindi y Olesen 2010; A
Iglesias, Quiroga, y Schlickenrieder 2010; Ana Iglesias et al. 2010). Variability in yields is
expected generally to increase, both in Southern and Northern Europe, due to extreme
climatic events and other factors, including pests and diseases (Kristensen et al., 2010;
Ferrise et al., 2011; Moriondo et al., 2011). Adaptation choices are complex and priorities
need to be established at the regional level to respond to specific risks and opportunities (Ana
Iglesias, Garrote, Diz, Schlickenrieder, y Martin-Carrasco 2011a; Ana Iglesias, Quiroga, y
Diz 2011).
[Agriculture]
1
Intensive farming systems in western and central Europe generally have a low sensitivity to
climate change, because a given change in temperature or rainfall have modest impact
(Chloupek et al., 2004), and because the farmers have resources to adapt and compensate by
changing management (Reidsma et al., 2010). However, there may be considerable difference
in adaptive capacity between cropping systems and farms depending on their specialisation
(Reidsma et al., 2008). Intensive systems in cool climates may therefore respond favourably
to a modest climatic warming (Olesen and Bindi, 2002). On the other hand some of the
farming systems currently located in hot and dry areas are expected to be most severely
affected by climate change. There is a large variation across the European continent in
climatic conditions, soils, land use, infrastructure, political and economic conditions. These
differences are expected also to greatly influence the responsiveness to climatic change
(Olesen et al., 2011; Trnka et al., 2011a).
The indicators selected to evaluate the impact of climate change on agriculture include the
rate of change of the crop growing season length, the timing of the cycle of agricultural crops
(agrophenology), the size and variability in crop yield, the rate of change of the
meteorological water balance, which indicates water requirements and water limitation of
crops. The indicators have been chosen based on four key issues: (1) identification of the
main drivers of agricultural change, (2) information needed to respond to adaptation policy
questions, (3) availability of relevant data, and (4) their ability to clearly show past changes
and indicate likely future trends. Table x summarises the
2
[Climate impacts on sectors and policies]
Table X: Summary Agricultural Indicators Observations, Projections, Adaptation options (to be
completed)
Indicator
Indicator key aspects
Reasons for Concern
Observations
Projections
Adaptation
Growing season
Rate of change of
crop growing season
length
Implications for
suitability of crop
species/cultivars
Growing Season is
changing
Likely increase in
some parts of Europe
Changes to crop
species and cultivars
Changes in
management
Agrophenology
Changes in length of
crop growth phases or
onset
Importance of
conditions during
growth phases
Flowering is
occurring earlier
Shortening of crop
growth phases
Changes in crop
cultivars
Changes in
management
Yield-variability
Yield changes due to
climate change /
climate events
Food commodity and
security implications
Crop yield variability
increases observed
Increasing variability
due to climate change
Changes in crop
cultivars, species
Changes in
management
Water
requirement
(irrigation)
Use proxy, rate of
change of the
meteorological water
balance
Potential changes in
irrigation needs have
to be taken into
account in deciding
appropriate crops and
is relevant for
irrigation
infrastructure/
efficiency
Mediterranean and
parts of Central
Europe experience an
increase in the water
required from
irrigation
Overall expected
increases in
temperature
throughout Europe
are likely to increase
evapo-transpiration
rates, thereby also
increasing water
requirements
Water use efficiency,
distribution efficiency
Changes in
management
Water limitation
of crops
Crop yield limitation
due to water
Water as limiting
factor in crop
productivity; crop
suitability
implications
Crop production is at
least moderately
water limited in many
regions and
especially in the
south
Crop water limitation
is projected to worsen
across the southern
part of Europe
Water use efficiency,
distribution efficiency
infrastructure
improvements
Changes in
management
[Agriculture]
3
6.1.2
Growing Season for Agricultural Crops
Key messages

Research indicates that the growing season of a number of agricultural crops in Europe is
changing

Studies have shown that the growing season in is likely to increase throughout most of Europe
due to earlier onset of growth in spring and later senescence in autumn
Relevance
Increasing air temperatures are significantly affecting the duration of the growing season over
large areas of Europe (Scheifinger et al., 2003). The duration of the growing season is for a
large part of Europe defined by the duration of the period with temperatures above a certain
threshold. In terms of the functioning of many plant species, e.g. for flowering, it is the
duration of the frost-free period that is important. However, active growth of plants requires
higher temperatures, and for most of the temperate crops grown in Europe a threshold
temperature of 5 ºC can be used, although growing of tropical crops like maize and sorghum
requires even higher temperatures (Trnka et al., 2011a).
A warming of the climate is reported mainly to result in an earlier start of the growing season
in spring and a longer duration in autumn (Jeong et al., 2011; Trnka et al., 2011c). A longer
growing season allows the proliferation of species that have optimal conditions for growth
and development and can thus increase their productivity or number of generations (e.g., crop
yield, insect population). This will in many cases also allow for introduction of new species
previously unfavourable due to low temperatures or short growing seasons. This is both
relevant for introduction of new crops, but will also affect the spreading of weeds, insect
pests and diseases (Roos et al., 2011). Changes in management practices, e.g. changes in the
species grown, different varieties, or adaptations of the crop calendar, can counteract the
negative effects of a changing growing season (pests) and capture the benefits (agricultural
crops).
Past trends
Many studies report a lengthening of the period between the occurrence of the last spring
frost and the first autumn frost. This has occurred in recent decades in several areas in Europe
and more generally in the northern hemisphere (e.g., Root et al., 2003; Trnka et al., 2011c).
Studies of changes in the growing season based on remote sensing shown a spatial pattern in
Europe, with western continental areas showing last freeze dates getting earlier faster, some
central areas having last freeze and first leaf dates progressing at about the same pace, while
in parts of Northern and Eastern Europe first leaf dates are getting earlier faster than last
freeze dates (Schwartz et al., 2006). Across all of Europe, the delay in end of the season of
4
[Climate impacts on sectors and policies]
the period 1992-2008 by 8.2 days was more significant than the advanced start of the season
by 3.2 days (Jeong et al, 2011).
An analysis of the frost free period in Europe between 1975 and 2010 shows a general and
clear increasing trend. The trend is not uniformly spread over Europe. The highest rates of
change (larger than 0.8 days per year) were recorded in central and southern Spain, central
Italy, along the Atlantic shores, and in the British Isles, Denmark, central parts of Europe and
in Turkey (Map X1). The map in Figure 1 shows that there are also areas in Europe with an
apparent trend for reductions in the frost free period. However, these trends are not
significant.
Map X1. The rate of change (number of days per year) of the number of frost-free days per
year as actually recorded during the period 1975–2010.
Projections
Following the observed trends and in line with projections for additional temperature
increase, a further lengthening of the growing season (both an earlier onset of spring and a
delay of autumn) as well as a northward shift of species is projected. The latter is already
widely reported (Aerts et al., 2006; Odgaard et al., 2011; Olesen et al., 2011). Results from
[Agriculture]
5
climate change projections show that the date of last frost in spring will advance by about 510 days by 2030 and by 10-15 days by 2050 thoughout most of Europe (Trnka et al., 2011a).
The extension of the growing season is expected to be of particular beneficial in northern
Europe, where a longer duration for crop growth allows new crops to be cultivated and where
water availability is not restricting growth (Olesen et al., 2011). I parts of the Mediterranean
area, the cultivation of some crops will under a milder climate be shifted into the winter
season (Minguez et al., 2007), which in these areas can offset some of the negative impacts of
heatwaves and droughts during summer. Other areas of Europe such as Western France and
parts of South-Eastern Europe (Hungary, Bulgaria, Romania, Serbia, etc.) will experience
yield reductions from hot and dry summers without the possibility of shifting the crop
production into the winter seasons.
Adaptation needs and options
The main adaptations to changes in duration of the growing season and the start and end of
the frost free season are changes in the crop species and varieties grown and the timing of
crop management operations. A northward shift in cultivation of temperature sensitive
species is therefore projected (Olesen et al., 2007). In particular, in southern Europe
adaptations may include changes in crop species that relate to major changes in the timing of
crop cultivations, e.g. replacing winter with spring wheat) (Minguez et al., 2007). In general,
there will be changes in cultivars and sowing dates (e.g. for winter crops, sowing the same
cultivar earlier, or choosing cultivars with a longer growth cycle; for summer irrigated crops,
earlier sowing for preventing yield reductions or reducing water demand (Olesen et al..,
2007; Kaukoranta and Hakala, 2008).
6
[Climate impacts on sectors and policies]
6.1.3
Agrophenology
Key messages

Flowering of a number of different crops is occurring earlier

A shortening of phases of crop growth in many crops can be expected, and this is particularly
detrimental to grain yield for shortening of the grain filling phase

Adaptation needs to include changes in management and potential changes in crop cultivars
Relevance
Changes in crop phenology provide important evidence of responses to recent regional
climate change (Menzel et al., 2003). Although phenological changes are often influenced by
management practices, in particular sowing date and choice of cultivar, recent warming in
Europe has clearly advanced a significant part of the agricultural calendar. Specific stages of
growth (e.g. flowering, grain filling) are particularly sensitive to weather conditions and
critical for final yield. The timing of the crop cycle (agrophenology) determines the
productive success of the crop. In general, a longer crop cycle is strongly correlated with
higher yields, since a longer cycle permits maximum use of the available thermal energy,
solar radiation and water resources. For cereals yields respond particularly to the duration of
the grain filling period (Kristensen et al., 2011). The impacts of unfavourable meteorological
conditions and extreme events vary considerably, depending on the timing of occurrence and
the development stage of the crops. However, shortening of the growth period can also help
avoid summer stress conditions in areas prone to drought.
European farmers have already adapted their practices to the changing climate by selecting
suitable varieties or adapting the crop calendar, and can be expected to do so increasingly in
the future.
Past trends
Several studies have collected data and observed changes in the phenological phases of
several perennial crops in Europe, such as the advance in the start of the growing season of
fruit trees (2.3 days/10 years), cherry tree blossom (2.0 days/10 years), and apple tree
blossom (2.2 days/10 years), in line with increases of up to 1.4 ºC in mean annual air
temperature in Germany (Chmielewski et al., 2004). Sowing or planting dates of several
agricultural crops have been advanced, by 5 days for potatoes in Finland, 10 days for maize
and sugar beet in Germany and 20 days for maize in France (IPCC, 2007).
[Agriculture]
7
An analysis of the modelled flowering date for winter wheat in Europe between 1975 and
2010 shows a general and clear increasing trend., which is most pronounced in northwestern
Europe (Map X2). In large parts of Europe the modelled flowering date has advanced by
more 0.3-0.5 days per year. This modelled advance in flowering date probably exceeds what
is observed in practice, where day length responses in the plants and farmers choices of
cultivars with longer growth duration will modify this response.
Map X2. Modelled change of flowering date for winter wheat 1975-2010.
Projections
With the projected warming of the climate in Europe, further reductions in the number of
days required for flowering in cereals (anthesis) and maturity may be expected throughout
Europe (Fig X3). The modelled changes in flowering dates in Figure X3 include the expected
effects of daylength reponse and changes in cultivar choice on flowering and maturity dates.
The flowering date for winter wheat is projected to show the greatest advance in the western
parts of Europe, but with a large uncertainty associated with the projected climate change.
The advance in maturity date is larger than the advance in flowering date, leading to a
shortening of the grain filling period, which will negatively affect yields. Semenov et al.
(2009) used another phenology model and other climate change projections for 2050, but
8
[Climate impacts on sectors and policies]
found similar changes in flowering date for winter wheat for England and Wales of 14-16
days.
Figure X3. Model estimated mean change in dates of flowering and full maturation for winter
wheat for the period 2031-50 compared with 1975-1994 for the KNMI and Hadley Centre
(HC) climate model projections under the A1B scenario (Olesen et al., 2011).
Adaptation needs and options
The main adaptation option to changes in flowering and maturity dates are choice of sowing
date for spring sown crops, and breeding of varieties with a longer growth duration, both for
the phase until flowering and for the grain filling phase from flowering to maturity.
[Agriculture]
9
6.1.4
Crop – yield variability (CLIM 032)
Key messages

Impact on regional crop suitability and productivity

Extreme climatic events including droughts, floods, storms, have had a considerable impact on
productivity during the first decade of the 21st century

The intensity and frequency of extreme weather events, flooding and droughts is expected to
increase and will necessitate relevant adaptation measures to reduce and prevent losses
Relevance
Crop yields are a function of climatic and environmental conditions and depend also on
agricultural management decisions, technology and inputs, such as fertilizers and pesticides.
Climate change is expected to have an impact on precipitation and temperature as well as on
the frequency and intensity of extreme events such as heat waves, droughts, floods, heavy
storms and other environmental changes (Beniston et al. 2007). This will impact crop yields
in terms of quantity as well as quality and may lead to crop yield differences from one year to
the next (Sonia Quiroga y Iglesias 2009; Ana Iglesias y Quiroga 2007), which will also have
important economic consequences (Ciscar et al. 2011; Ana Iglesias 2010).
Past trends
The past century saw important productivity increases in many parts of the world. However,
climate change has been linked in some studies to a change in crop yield. At the global level
for the period 1961 – 2002, temperature and precipitation have been estimated to explain
approximately 30% of interannual variation of yields for the six most widely cultivated crops
and a clear negative correlation between global yields and increased temperatures has been
identified for wheat, maize and barely (Lobell and Field 2007). Using crop yield models, it
was found that for 1980 – 2008, maize and wheat yields declined 3.8% and 5.5%,
respectively, when compared to expected yields without climate change (Lobell, Schlenker, y
Costa-Roberts 2011)In Europe, variable weather patterns and occasional extreme events over
the past decades have been associated with yield variability and higher temperatures have
been linked to negative impacts on yields of grain and seed crops (Peltonen-Sainio et al.
2010).
Projections
The future likely impact of a changing climate on crop yield depends on the direction and
size of the change that is to be experienced as well as a combination of other environmental,
regional, local and farm-level conditions and factors (Reidsma et al. 2010). Studies using
10
[Climate impacts on sectors and policies]
crop models to provide projections of changes in crop productivity have been undertaken for
many years (Semenov and Porter 1995). At the global level, even under different future
scenarios, regional winners and losers can be identified (FigureX), (Ana Iglesias, Quiroga, y
Diz 2011) Often however, analyses concentrate on one particular region or crop. For
instance, for winter wheat in Denmark it has been projected that grain yield decreases 3.6%
by 2020 and 8.0% by 2040, compared to 1985 yields (Kristensen, Schelde, y Olesen 2011).
At the European level, for many environmental zones, a clear picture of deterioration of
agroclimatic conditions from increased drought stress and a shortening of active growing
season begins to emerge. Some results also suggest a risk of an increasing number of
unfavourable years for agricultural production in many European climatic zones, resulting in
possible year-to-year yield variability (M. Trnka, Olesen, et al. 2011).
FigureX shows projected land productivity change aggregated at the country level for an average A1B and E1
scenarios for the 2080s without considering adaptation (Ana Iglesias, Quiroga, y Diz 2011).
Often however, analyses concentrate on one particular region or crop. For instance, for winter
wheat in Denmark it has been projected that grain yield decreases 3.6% by 2020 and 8.0% by
2040, compared to 1985 yields (Kristensen, Schelde, y Olesen 2011). In Macedonia, a recent
study analysed the likely impact of different future climate scenarios on wheat yield using
Decision Support System for Agrotechnology Transfer (DSSAT) The outcome of this
exercise, which also contemplated different adaptation responses shows a wide range of yield
responses for different future climate scenarios and is shown in Figure X (further details to be
incorporated).
[Agriculture]
11
Scenario Medium (5, 6, 7, 8), adaptation level-1,
level0, level+1, dryland and irrigated
Scenario Medium (5, 6, 7, 8), adaptation level+2,
level+3, dryland and irrigated
Scenario high (9, 10, 11, 12), adaptation level-1,
level0, level+1, dryland and irrigated
Scenario high (9, 10, 11, 12), adaptation level+2,
level+3, dryland and irrigated
Figure X. Yield at maturity for wheat in Macedonia for medium (top) and high (bottom) climate change
scenarios for four time slices (2010, 2020, 2030, 2040) for both dryland and irrigated agriculture and
considering different adaptations (level -1/0/1 in left column and +2/+3 in right column). Bars indicate
the range of values; orange stars indicate the 50th percentile (Further details to be incorporated and other
sites to be chosen)
At the European level, for many environmental zones, a clear picture of deterioration of
agroclimatic conditions from increased drought stress and a shortening of active growing
season begins to emerge. Some results also suggest a risk of an increasing number of
unfavourable years for agricultural production in many European climatic zones, resulting in
possible year-to-year yield variability (M. Trnka, Olesen, et al. 2011).
Adaptation needs and options
Adaptation to a change in crop-yield variability as a result of changes in climate and extreme
events involves both anticipating and planning for the changes and identifying and
12
[Climate impacts on sectors and policies]
implementing appropriate measures to facilitate adaptation. This will be important for the
future and competitiveness of European agriculture and has implications for global food
security and international trade.
Changing varieties that are more adapted to the particular climatic conditions in question or
in the agricultural management decisions (sowing date, fertilization, irrigation, drainage) as
well as modifications to land allocation and farming system are adaptation options that
should be evaluated to reduce negative crop-yield variability (Bindi y Olesen 2010). More
specifically, for many parts of Europe, projections point to a need for adaptive measures to
increase soil water availability or drought resistance of crops ((M. Trnka, Olesen, et al. 2011).
Figure X (update) shows the sensitivity of maize and wheat yields to climate change,
spanning a range of temperature changes and considering cases where adaptation measures in
terms of changes in planting dates, crop varieties and shifts from rain-fed to irrigated
conditions are implemented.
[Agriculture]
13
Figure X: Sensitivity of cereal yields to climate change for maize and wheat (update graph
from JRC or other study - TBC)
14
[Climate impacts on sectors and policies]
6.1.5
Water requirement / (CLIM033)
Key messages

Italy and the Iberian Peninsula and parts of Central Europe have experienced an increase in the
volume of water required from irrigation in order to ensure that crop growth is not limited by
water stress

Overall expected increases in temperature throughout Europe will lead to increase in
evapotranspiration rates, thereby also increasing water requirements for crops.

The trend of increasing water requirements is expected to be more acute in Southern Europe,
where the extent of the suitability of rainfed agriculture will decrease and irrigation requirements
will increase. This will coincide with a general reduction in water availability
Relevance
Climate change will affect agriculture through changes in CO2 concentration as well as
changes in temperature, radiation and precipitation. The global demand for water will also be
affected by socio-economic changes such as population and income increases and changes in
dietary preferences. Increasing demands for water by industrial and urban users, and water
for the environment will intensify competition. At the same time, water scarcity is increasing
in several important agricultural areas (Ana Iglesias et al. 2006; Giupponi y Shechter 2003).
Adaptation options include water use efficiency improvements, infrastructure improvements
as well as measures to improve soil properties, among others.
Past trends
Although consistent observations of water demand for agriculture do not currently exist for
Europe, trends can be evaluated using meteorological data. Figure X provides an estimate of
the change of the volume of water required from irrigation in order to ensure that crop growth
is not limited by water stress for the April-September growing season. For the period
considered (1975 – 2010), particularly Italy and the Iberian Peninsula but also parts of
Central Europe experience an increase in the volume of water required from irrigation in
order to ensure that crop growth is not limited by water stress.
[Agriculture]
15
Map X: Rate of change of themeterological water balance 1975 - 2010
Note: The rate of change of the “meterological water balance,” expressed in m3 ha-1 y-1. The
map provides an estimate increase (red in map) or decrease (blue in map) of the volume of
water required from irrigation in order to ensure that crop growth is not limited by water
stress. Source: MARS/STAT database
Projections
Ongoing changes in consumer preferences, particularly in developing countries, has been
suggested as one of the main drivers determining future agricultural water use, especially
since livestock products, sugar, and oils typically require more water to produce than cereals
roots or tubers (de Fraiture y Wichelns 2010). Numerous climate scenarios foresee a likely
increase in precipitation in the north and a decrease in southern Europe, particularly during
the summer. Droughts are projected to become more severe and persistent in most parts of
Europe by the end of the 21st century, except in the most northern and north-eastern regions.
Estimations of irrigation demand for all of Europe are difficult to attain but regional
projections can provide insight into possible trends (Iglesias et al. 2006). For the
Mediterranean region, in the framework for the CIRCE project (Climate Change and Impact
Research: the Mediterranean Environment), an analysis of water availability and reliability
for meeting irrigation demands once urban demands are satisfied (based on 300L per capita
16
[Climate impacts on sectors and policies]
per day base) was carried out (Quiroga Gomez et al. 2010; Ana Iglesias et al. 2011; Quiroga,
Fernandez-Haddad and Iglesias 2011). The advantage of the approach used is that the model
(WAPA) combines estimations of future demographic and economic developments with
changes expected due to climate change. Figure x, shows the per-unit change in runoff for
2021 – 2050 with respect to the control scenario as well as the per unit change in water
availability considering urban demand as primary. In many European basins, the
proportional reduction of water availability is larger than the reduction in mean annual
runoff, implying that the use of water for other purposes such as irrigation would be curtailed
more than the reduction in annual runoff considering priority of urban demand (Iglesias et al.
2011; Quiroga et al. 2011)
Figure X Per unit reduction of runoff (above) and water availability for irrigation (below) in climate change
scenario (2070-2100) with respect to control run (1960-1990) for DMI model in Mediterranean European basins
Irrigation demand estimations are necessary at detailed spatial scales and different climatic or
agricultural zones. Figure X shows the evolution of annual irrigation requirement for wheat
in three sites in Macedonia representing Alpine, Continental and Mediterranean climates. An
appreciable increase in irrigation demand can be expected by 2040 under the medium and
high scenarios for both the Continental and Mediterranean sites evaluated.
Alpine AEZ
Continental AEZ
Mediterranean AEZ
(Solunska Glava, Macedonia)
(Kriva Palanka, Macedonia)
(Shtip, Macedonia)
[Agriculture]
17
300.00
25.00
wheat total irrgi damand
(mm/yr)
s00
s01
250.00
20.00
400.00
wheat total irrgi damand
(mm/yr)
s04
s05
150.00
s06
s05
200.00
s06
s05
s07
100.00
s08
s07
150.00
s07
s08
100.00
s09
s08
s1050.00
s11
s12 0.00
s10
s11
s12 0.00
0.00
s01
250.00
s04
s09
50.00
s10
5.00
s00
s02
s03
200.00
s04
10.00
wheat total irrgi damand
(mm/yr)
s02
300.00
s03
s02
15.00
s00
350.00
s01
1
1
Climate scenario Time-slice
s03
s06
s09
s11
s12
1
Figure Legend
700.00
600.00
500.00
400.00
300.00
200.00
100.00
0.00
pasture total irrgi damand
base
1992-2002
(mm/yr)
low
2010
s00
s01
low
2020
s02
low
2030
s03
low
2040
s04
medium
2010
s05
medium
2020
s06
medium
2030
s07
medium
2040
s08
high
2010
s09
high
2020
s10
high
2030
s11
high
2040
s12
1
Figure X. Change
in total irrigation water requirements per year in mm for wheat for three locations
in Macedonia representing Alpine, Continental and Mediterranean climates and for baseline
conditions (1992 – 2002) as well as for four time-slices (2010, 2020, 2030, 2040) and three different
climate change scenarios (low, medium high). (Other sites to be chosen from different European
regions)
Adaptation needs and options
Concepts such as water productivity (Molden et al. 2010; Siebert y Döll 2010), water
footprint and water trade (Chapagain y Hoekstra 2008) can provide a basis to evaluate the
need to shift the production of certain crops to other regions where climatic conditions are
more amenable to certain cultivars. Also, the implementation of measures such as water
harvesting, supplemental irrigation, deficit irrigation, precision irrigation techniques and soil–
water conservation practices will reduce overall water losses and can counterbalance some of
the increased demand due to climatic factors (Chapagain y Hoekstra 2008; Molden et al.
2010), especially considering that gross irrigation demands have been estimated to be 1.3 –
2.5 higher than actual field requirements, due to inefficient transport and different water
18
[Climate impacts on sectors and policies]
management approaches (Wriedt et al. 2009). Planning, including the development and
implementation of guidelines and management plans can help to reduce possible yield losses
in cases such as drought or flood events (Ana Iglesias, Garrote, y Cancelliere 2009).
[Agriculture]
19
6.1.6
Water limitation of crops
Key messages

Already today, crop production is at least moderately water limited in many regions and
especially in the south

Crop water limitation is projected to worsen across the southern part of Europe

In the temperate and northern latitudes, a water-driven increase in crop production is likely
Relevance
Crop water is water needed by a crop for growth and it is extracts water from the soil. It is
dependent on weather conditions, soil water, the crop species and the particular growth stage
of the crop. Providing a measure of crop production limited by water can give an indication
of the hotspots where water limitation is currently or will in the future play an important role
in determining agricultural production.
Past trends
Already today, crop production is at least moderately water limited - defined as a ratio of
actual to maximum production of < 0.7 - in many regions and especially in the south. Over
most of the Mediterranean region, actual production is less than half the production that
would be possible in the absence of water limitation - a ratio of < 0.5: in contrast, crop
production is hardly water limited in northern and north-western Europe where the ratio is >
0.8. (Gerten, 2009).
Projections
Crop water limitation is projected to worsen across the southern part of Europe. Streamflow
droughts will become more severe and persistent in most parts of Europe by the end of the
century, except in the most northern and north-eastern regions. Most of Europe, except Spain,
Southern Italy and South-Eastern Europe is not expected to observe major changes in mean
annual river flow a reduction in river flows is projected for the summer in most areas of
Europe. (Feyen and Dankers, 2009; Feyen and Dankers, 2010). When considering different
future socio-economic scenarios and developments, competition for limited water resources
becomes more severe in water-limited areas. While water resources that can potentially be
used for irrigation will diminish in the regions for which crop water limitation is projected to
increase, the absolute demand for irrigation is expected to increase and thereby contribute
additionally to water scarcity problems.
The probability of the occurrence of days with water deficit (defined as ETa/ETr ratio is less
than 0.4) from April to June was projected to increase in the Mediterranean (M. Trnka,
20
[Climate impacts on sectors and policies]
Olesen, et al. 2011). Despite lower summer precipitation expected by 2050s across Europe
and higher probability of dry days, it may be possible that yield losses from drought become
lower as winter wheat, for instance, will mature earlier and avoid severe drought (Mikhail A.
Semenov y Shewry 2011).
Adaptation needs and options
Without adaptation measures, crop yields are likely to decline due to water shortages,
particularly in regions expected to experience reductions in water availability during critical
growing periods, such as southern Europe. Adaptation can encompass improved water use in
rain-fed agriculture, increases in irrigated areas, as well as increases in irrigation efficiency
through improved management approaches.
Figure X. Water limitation of crop primary production in Europe under rain-fed conditions
Note: Crop water limitation is expressed as ratio between actual and theoretical production
averaged over all crop types
Source: Gerten 2009
[Agriculture]
21
6.1.7
References
Aerts, R., Cornelissen, J.H.C., Dorrepaal, E., 2006. Plant performance in a warmer world:
general responses of plants from cold, northern biomes and the importance of winter and
spring events. Plant Ecology 82: 65–77.
Bindi, M., Olesen, J.E., 2011. The response of agriculture in Europe to climate change.
Regional Environmental Change 11 (suppl. 1): S151-S158.
Brisson, N., Gate, P., Gouache , D., Charmet, G., Oury, F.-X., Huard, F., 2010. Why are
wheat yields stagnating in Europe? A comprehensive data analysis for France. Field Crop
Research 119: 201-212.
Chloupek, O., Hrstkova, P., Schweigert, P., 2004. Yield and its stability, crop diversity,
adaptability and response to climate change, weather and fertilisation over 75 years in the
Czech Republic in comparison to some European countries. Field Crops Research 85: 167190.
Chmielewski, F.-M., Műller, A. and Bruns, E., 2004. Climate changes and trends in
phenology of fruit trees and field crops in Germany, 1961–2000. Agriculture and Forest
Meteorology 121: 69–78.
Ciscar JC, Iglesias A, Feyen L, Szabó L, Van Regemorter D, Amelung B, Nicholls R,
Watkiss P, Christensen OB, Dankers R, Garrote L, Goodess CM, Hunt A, Moreno A,
Richards J, Soria A (2011) Physical and economic consequences of climate change in
Europe, Proceedings of the National Academy of Sciences (PNAS), Published online before
print January 31, 2011, doi: 10.1073/pnas.1011612108 PNAS January 31, 2011. Ciscar et al.
www.pnas.org/cgi/content/short/1011612108.
Ferrise, R., Moriondo, M., Bindi, M., 2011. Probabilistic assessments of climate change
impacts on durum wheat in the Mediterranean region. Natural Hazards and Earth Systems
Sciences 11: 1293-1302.
Iglesias A (2010) Climate Change and Agriculture: An Economic Analysis of Global
Impacts, Adaptation and Distributional Effects. European Review of Agricultural Economics
2010 37: 421-423
Iglesias A, Cancelliere A, Cubillo F, Garrote L, Wilhite DA (2009) Coping with drought risk
in agriculture and water supply systems: Drought management and policy development in the
Mediterranean. Springer, The Netherlands
Iglesias A, Diz A, Quiroga S (2011) Looking into the future of agriculture. European Review
of Agricultural Economics 38(3): 427-447.
Iglesias A, Garrote L, Flores F, Moneo M (2007) Challenges to manage the risk of water
scarcity and climate change in the Mediterranean. Water Resources Management, 21(5), 227288
22
[Climate impacts on sectors and policies]
Iglesias A, Moneo M, Quiroga S, Garrote L (2011) Re-thinking the impacts of climate
change on agriculture in the European Union. Climatic Change. DOI: 10.1007/s10584-0110344-x
Iglesias A, Quiroga S (2007) Measuring cereal production risk form climate variability across
geographical areas in Spain. Climate Research 34, 47-57.
Iglesias A, Quiroga S, Schlickenrieder J (2010) Climate change and agricultural adaptation:
assessing management uncertainty for four crop types in Spain, Climate Research. 44, 83–94.
doi: 10.3354/cr00921
Iglesias A., Mougou R., Moneo M. and Quiroga, S. (2010). Towards adaptation of agriculture
of climate change in the Mediterranean. Regional Environmental Change in press Published
online first DOI 10.1007/s10113-010-0187-4
Iglesias, A., Quiroga, S. (2007) Measuring cereal production risk form climate variability
across geographical areas in Spain. Climate Research 34, 47-57.
IPCC, 2007. Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of
Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on
Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E.
Hanson, Eds., Cambridge University Press, Cambridge, UK.
Jeong, S.J., Ho, C.H., Gim, H.J., 2011. Phenology shifts at start vs. end of growing season in
temperate vegetation over the Northern Hemisphere for the period 1982-2008. Global
Change Biology 17: 2385-2399.
Kaukoranta, T., Hakala, K., 2008. Impact of spring warming on sowing times of cereal,
potato and sugar beet in Finland. Agriculture and Food Science 17: 165-176.
Kristensen, K., Schelde, K., Olesen, J.E., 2011. Winter wheat yield response to climate
variability in Denmark. Journal of Agricultural Science 149: 33-47.
Menzel, A., Jakobi, G., Ahas, R., Scheifinger, H., Estrella, N., 2003. Variations of the
climatological growing season (1951–2000) in Germany compared with other countries.
International Journal of Climatology 23: 793–812.
Minguez, M.I., Ruiz-Ramos, M., Díaz-Ambrona, C.H., Quemada, M., Sau, F., 2007. Firstorder impacts on winter and summer crops assessed with various high-resolution climate
models in the Iberian peninsula. Climatic Change 81 (suppl 1): 343-355.
Moriondo, M., Giannakopolous, C., Bindi, M., 2011. Climate change impact assessment: the
role of climate extremes in crop yield simulation. Climatic Change 104: 679-701.
Odgaard, M.V., Bocher, P.K., Dalgaard, T., Svenning, J.C., 2011. Climatic and non-climatic
drivers of spatiotemporal maize-area dynamics across the northern limit for maize production
– A case study from Denmark. Agriculture Ecosystems & Environment 142: 291-302.
[Agriculture]
23
Olesen, J.E., Bindi, M., 2002. Consequences of climate change for European agricultural
productivity, land use and policy. European Journal of Agronomy 16: 239-262.
Olesen, J.E., Børgesen, C.D., Elsgaard, L., Palosuo, T., Rötter, R., Skjelvåg, A.O., Peltonen-Sainio,
P., Börjesson, T., Trnka, M., Ewert, F., Siebert, S., Brisson, N., Eitzinger, J., van der Fels-Klerx, H.J.,
van Asselt, E., 2011. Changes in flowing and maturity time of cereals in Northern Europe under
climate change. Food Additives and Contaminants (submitted).
Olesen, J.E., Carter, T.R., Diaz-Ambrona, C.H., Fronzek, S., Heidmann, T., Hickler, T., Holt,
T., Minguez, M.I., Morales, P., Palutikof, J., Quemada, M., Ruiz-Ramos, M., Rubæk, G.,
Sau, F., Smith, B., Sykes, M., 2007. Uncertainties in projected impacts of climate change on
European agriculture and ecosystems based on scenarios from regional climate models.
Climatic Change 81, Suppl. 1, 123-143.
Olesen, J.E., Trnka, M., Kersebaum, K.C., Skjelvåg, A.O., Seguin, B, Peltonen-Saino, P.,
Rossi, F., Kozyra, J., Micale, F., 2011. Impacts and adaptation of European crop production
systems to climate change. European Journal of Agronomy 34: 96-112.
Peltonen-Sainio, P., Jauhianinen, J., Trnka, M., Olesen, J.E., Calanca, P.L., Eckersten, H.,
Eitzinger, J., Gobin, A., Kersebaum, C., Kozyra, J., Kumar, S., Marta, A.D., Micale, F.,
Schaap, B., Seguin, B., Skjelvåg, A., Orlandini, S., 2010. Coincidence of variation in yield
and climate in Europe. Agriculture, Ecosystems & Environment 139: 483-489.
Quiroga S, Fernández-Haddad Z, Iglesias A (2011) Crop yields response to water pressures
in the Ebro basin in Spain: risk and water policy implications. Hydrology and Earth System
Sciences (HESS), 15, 505-518, 2011
Quiroga S, Garrote L, Iglesias A, Fernández-Haddad Z, Schlickenrieder J, de Lama B, Mosso
C, Sánchez-Arcilla A (2011) The economic value of drought information for water
management under climate change: a case study in the Ebro basin. Natural Hazards and Earth
System Sciences (NHESS), 11, 643-657.
Reidsma, P., Ewert, F., 2008. Regional farm diversity can reduce vulnerability of food
production to climate change. Ecology and Society 13: 38.
Reidsma, P., Ewert, F., Lansink, A.O., Leemans, R., 2010. Adaptation to climate change and
climate variability in European agriculture: The importance of farm level responses.
European Journal of Agronomy 32: 91-102.
Roos, J., Hopkins, R., Kvarnheden, A., Dixelius, C., 2011. The impact of global warming on
plant diseases and insect vectors in Sweden. European Journal of Plant Pathology 129: 9-19.
Root, T. L., Price, J. T., Hall, K. R., Schneider, S. H., Rosenzweig, C., Pounds, A., 2003.
Fingerprints of global warming on wild animals and plants. Nature 421: 57–60.
Scheifinger, H., Menzel, A., Koch, E., Peter, Ch., 2003. Trends of spring time frost events
and phenological dates in Central Europe. Theoretical and Applied Climatology 74: 41–51.
24
[Climate impacts on sectors and policies]
Schwartz, M.D., Ahas, R., Aasa, A., 2006. Onset of spring starting earlier across the Northern
Hemisphere. Global Change Biology 12: 343-351.
Trnka, M., Brazdil, R., Dubrovsky, M., Semeradova, D., Stepanek, P., Dobrovolny, P.,
Mozny, M., Eitzinger, J., Malek, J., Formayer, H., Balek, J., Zalud, Z., 2011b. A 200-year
climate record in Central Europe: implications for agriculture. Agronomy for Sustainable
Development 31: 631-641.
Trnka, M., Eitzinger, J., Semeradova, D., Hlavinka, P., Balek, J., Dubrovsky, M., Kubu, G.,
Stepanek, P., Thaler, S., Mozny, M., Zalud, Z., 2011b. Expected changes in agroclimatic
conditions in Central Europe. Climatic Change 108: 261-289.
Trnka, M., Olesen, J.E., Kersebaum, K.C., Skjelvåg, A.O., Eitzinger, J., Seguin, B., PeltonenSainio, P., Orlandini, S., Dubrovsky, M., Hlavinka, P., Balek, J., Eckersten, H., Cloppet, E.,
Calanca, P., Rötter, R., Gobin, A., Vucetic, V., Nejedlik, P., Kumar, S., Lalic, B., Mestre, A.,
Rossi, F., Alexandrov, V., Kozyra, J., Schaap, B., Zalud, Z., 2011a. Agroclimatic conditions
in Europe under climate change. Global Change Biology 17: 2298-2318.
[Agriculture]
25