Water-limited crop yield

Assessment versions

Published (reviewed and quality assured)

• No published assessments

Rationale

Justification for indicator selection

The production of biomass in crops is the result of the capture and conversion of solar energy through the process of photosynthesis. However, this process may be restricted by low (or high) temperatures or by water limitations. Crop yields are affected by the combined effects of changes in temperature, rainfall and atmospheric CO₂ concentration. In practice, the response depends on soil type, which can differ greatly in capacity for storing soil moisture, and on the possibilities for supplementary irrigation. Crop yield also depends on the timing of the crop growth and yield formation. Yields in cereal and oilseed crops respond particularly to the duration of the grain-filling period. The impacts of unfavourable meteorological conditions and extreme events vary considerably, depending on the timing of occurrence and the development stage of the crops. Changes in the occurrence of extreme events such as heat waves, droughts, heavy precipitation and floods will greatly affect crop yield leading to increased variability and economic consequences.

Scientific references

• No rationale references available

Indicator definition

• Projected changes in water-limited yield of winter wheat
• Projected changes in water-limited crop yield
• Probability of the occurrence of adverse agroclimatic conditions for wheat under baseline and projected climate

Units

• Percentage (%)
• Probability (unitless)

Policy context and targets

Context description

In April 2013, the European Commission (EC) presented the EU Adaptation Strategy Package. This package consists of the EU Strategy on adaptation to climate change (COM/2013/216 final) and a number of supporting documents. The overall aim of the EU Adaptation Strategy is to contribute to a more climate-resilient Europe.

One of the objectives of the EU Adaptation Strategy is Better informed decision-making, which will be achieved by bridging the knowledge gap and further developing the European climate adaptation platform (Climate-ADAPT) as the ‘one-stop shop’ for adaptation information in Europe. Climate-ADAPT has been developed jointly by the EC and the EEA to share knowledge on (1) observed and projected climate change and its impacts on environmental and social systems and on human health, (2) relevant research, (3) EU, transnational, national and subnational adaptation strategies and plans, and (4) adaptation case studies.

Further objectives include Promoting adaptation in key vulnerablesectors through climate-proofing EU sector policies and Promoting action by Member States. Most EU Member States have already adopted national adaptation strategies and many have also prepared action plans on climate change adaptation. The EC also supports adaptation in cities through the Covenant of Mayors for Climate and Energy initiative.

In September 2016, the EC presented an indicative roadmap for the evaluation of the EU Adaptation Strategy by 2018.

In November 2013, the European Parliament and the European Council adopted the 7^th EU Environment Action Programme (7^th EAP) to 2020, ‘Living well, within the limits of our planet’. The 7^th EAP is intended to help guide EU action on environment and climate change up to and beyond 2020. It highlights that ‘Action to mitigate and adapt to climate change will increase the resilience of the Union’s economy and society, while stimulating innovation and protecting the Union’s natural resources.’ Consequently, several priority objectives of the 7^th EAP refer to climate change adaptation.

Targets

No targets have been specified.

Related policy documents

• 7th Environment Action Programme
  DECISION No 1386/2013/EU OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 20 November 2013 on a General Union Environment Action Programme to 2020 ‘Living well, within the limits of our planet’. In November 2013, the European Parliament and the European Council adopted the 7 th EU Environment Action Programme to 2020 ‘Living well, within the limits of our planet’. This programme is intended to help guide EU action on the environment and climate change up to and beyond 2020 based on the following vision: ‘In 2050, we live well, within the planet’s ecological limits. Our prosperity and healthy environment stem from an innovative, circular economy where nothing is wasted and where natural resources are managed sustainably, and biodiversity is protected, valued and restored in ways that enhance our society’s resilience. Our low-carbon growth has long been decoupled from resource use, setting the pace for a safe and sustainable global society.’
• Climate-ADAPT: Adaptation in EU policy sectors
  Overview of EU sector policies in which mainstreaming of adaptation to climate change is ongoing or explored
• Climate-ADAPT: Country profiles
  Overview of activities of EEA member countries in preparing, developing and implementing adaptation strategies
• DG CLIMA: Adaptation to climate change
  Adaptation means anticipating the adverse effects of climate change and taking appropriate action to prevent or minimise the damage they can cause, or taking advantage of opportunities that may arise. It has been shown that well planned, early adaptation action saves money and lives in the future. This web portal provides information on all adaptation activities of the European Commission.
• EU Adaptation Strategy Package
  In April 2013, the European Commission adopted an EU strategy on adaptation to climate change, which has been welcomed by the EU Member States. The strategy aims to make Europe more climate-resilient. By taking a coherent approach and providing for improved coordination, it enhances the preparedness and capacity of all governance levels to respond to the impacts of climate change.
• EU Common Agricultural Policy (CAP) reform - basic regulations
  References to climate change particularly in Regulation 1307/2013 (direct payments for farmers), Regulation 1306/2013 (so-called horizontal issues such as funding and controls: Articles 12 and 93, Annex I) and Regulation 1305/2013 (rural development: Articles 5, 7, 15, 28, 34, 35, 53 and 55).

Methodology

Methodology for indicator calculation

The change in mean water-limited crop yield of winter wheat between the baseline period centred around year 2000 and a future period centred around 2030 has been estimated using four simulations (combination of two climate models HadGEM2 and MIROC and the crop model WOFOST at 25 km spatial resolution), with and without taking into account the effect of CO₂ fertilization. Crop variety and agro-management practice have been kept constant.

The mean relative changes in water-limited crop yield are simulated by the ClimateCrop model for the 2050s compared with 1961–1990 for 12 different climate model projections under the A1B emission scenario. The ClimateCrop model was applied to explore the combined effects of projected changes in temperature, rainfall and CO₂ concentration across Europe, considering effects of adaptation. The simulation assumes that the irrigated area remains constant, and the results combine the response of the key crops wheat, maize and soybean, weighted by their current distribution.

The frequency of adverse agroclimatic conditions for wheat is projected using the probability that at least one out of 11 types of adverse agroclimatic conditions occurs between sowing and majority of wheat (medium-ripening cultivar) under baseline climate and projected climate.

Methodology for gap filling

Not applicable

Methodology references

No methodology references available.

Data specifications

EEA data references

• No datasets have been specified here.

External data references

• Adverse weather conditions for European wheat production will become more frequent with climate change
• Assessing agriculture vulnerabilities for the design of effective measures for adaption to climate change - AVEMAC project
• A regional comparison of the effects of climate change on agricultural crops in Europe

Data sources in latest figures

Uncertainties

Methodology uncertainty

Not applicable

Data sets uncertainty

Crop yield and crop requirements for irrigation are affected not only by climate change, but also by management and a range of socio-economic factors. The effects of climate change on these factors therefore have to be estimated indirectly using agrometeorological indicators and through statistical analyses of the interaction between climatic variables and factors such as crop yield.

The projections of climate change impacts and adaptation in agriculture rely heavily on modelling, and it needs to be recognised that there is often a chain of uncertainty involved in the projections, which range from emissions scenarios, through climate modelling and downscaling, to assessments of impacts using an impact model. The extent of all these uncertainties is rarely quantified, even though some studies have assessed uncertainties related to individual components. The crop modelling community has only recently started addressing uncertainties related to modelling impacts of climate change on crop yield and the effect of possible adaptation options. Recently, the effects of extreme climate events have also been included in impact assessments, but other effects such as those related to biotic hazards (e.g. pests and diseases) still need to be explored.

Rationale uncertainty

No uncertainty has been specified