Technical Policy Briefing Notes - 7
Analytic Hierarchy Process
Case Studies
Policy Briefs
Analytic Hierarchy Process
Case Studies
The MEDIATION study has reviewed existing
literature examples that have applied AHP to
adaptation. The project has also undertaken two
case study applications, summarised in the
boxes below.
Case
Study 1 – Adaptation options for agriculture in the Guadiana
River Basin, Spain
The first case study was focused on the Guadiana river basin in south-central Spain, with an application of AHP to adaptation in the agricultural and water sectors. This basin is expected to be one of the most seriously affected by climate change in Spain, with potentially high impacts on irrigated agriculture. The case study began by specifying the adaptation strategies being considered by policy-makers at the national and regional level, representing the starting point for a stakeholderdriven appraisal and prioritization of potential options.
Options and criteria
The Government of Extremadura initiated its Climate Change Strategy in 2009, which included a Climate Change Adaptation Plan for the Agricultural Sector (Junta de Extremadura, 2011). This aimed to identify the main impacts on the sector and define adaptation measures to guarantee its viability, minimizing the negative consequences of climate change as well as maximizing potential new opportunities.
The Plan contained seven programmes to tackle adaptation to climate change for the agricultural sector in Extremadura: Increasing Water Availability; Management and Planning of New Crops; Reduction of Vulnerability against Extreme Climate Conditions; Plant Health; Research and Development; Training and Information for farmers; and Leveraging positive impacts. Drawing from these programmes and the specific measures they included, the AHP aimed to prioritize adaptation options in the Guadiana River Basin. Four options were identified according to their feasibility and their relevance for the area under study, and a range of criterion were chosen. These are summarised in the hierarchy tree in Figure 1.
Figure 1. AHP hierarchy for agricultural adaptation options.
The next step was to carry out a pairwise comparison, comparing individual elements to one another, with respect to their impact or importance on an element above them in the hierarchy. Firstly, participants were asked to compare the relative preference for each of the measures with every criterion. For example, for the first criterion, feasibility of legal and political implementation (of the chosen measure), participants compared one option against another in relation to the ability of each option to be designed, supported and implemented from a legal and political standpoint. This exercise was repeated with each of the six criteria. Secondly, participants were asked to assess the relative importance of each of the criteria with respect to the achievement of the goal. i.e. they compared the relative importance of each criteria for the adaptation of the agricultural sector to climate change in the Guadiana River Basin. Answers were processed using the decision-making software Expert Choice.
The results are shown below in Figure 2.
Figure 2. Aggregate results from the AHP exercise for adaptation options.
The aggregated results show that the options Choice of new crop varieties best suited to new climate conditions and Improving technical efficiency in the use of water were equal first position in the ranking. Creation of agricultural insurance systems ranks third and finally Increase reservoir storage capacity ranks fourth. Choice of new crop varieties best suited to new climate conditions and Improving technical efficiency in the use of water performed well under all selected criteria, ranking first except for financial feasibility and speed of implementation, whereas Creation of agricultural insurance systems ranked first due to its lower cost and ease of implementation. The Increase reservoir storage capacity option was ranked low in aggregate terms and was highly controversial and criticized by most respondents, who made reference to the high cost and large environmental impact of this option.
When analysing the criteria, the protection of environmental resources was the most influential criterion at the aggregate level with a weight of 35.4%, followed by financial feasibility and capacity to generate employment. The protection of environmental resources was the dominant overall criterion given support by all respondent groups, even farmers. Similarly financial feasibility was highly ranked by most groups, especially policymakers.
The AHP analysis showed that at an aggregate level, options related to private farming (new crops and irrigation efficiency) ranked highest, public-funded ‘hard’ measures (reservoirs) ranked lowest, and public ‘soft’ measures (insurance) fell in the middle. Environmental criteria were preferred to socioeconomic and technical criteria. There were, however, differences in the ranking between groups. Whilst environmental organisations and academics ranked climate change options similarly to the average aggregate, policy makers preferred ‘soft’ measures (insurance) and discarded large irrigation infrastructures (probably due to financial, political and environmental constraints). Farmers’ priorities were technically-oriented, giving the highest ranking to the construction of water storage infrastructure.
The first case study was focused on the Guadiana river basin in south-central Spain, with an application of AHP to adaptation in the agricultural and water sectors. This basin is expected to be one of the most seriously affected by climate change in Spain, with potentially high impacts on irrigated agriculture. The case study began by specifying the adaptation strategies being considered by policy-makers at the national and regional level, representing the starting point for a stakeholderdriven appraisal and prioritization of potential options.
Options and criteria
The Government of Extremadura initiated its Climate Change Strategy in 2009, which included a Climate Change Adaptation Plan for the Agricultural Sector (Junta de Extremadura, 2011). This aimed to identify the main impacts on the sector and define adaptation measures to guarantee its viability, minimizing the negative consequences of climate change as well as maximizing potential new opportunities.
The Plan contained seven programmes to tackle adaptation to climate change for the agricultural sector in Extremadura: Increasing Water Availability; Management and Planning of New Crops; Reduction of Vulnerability against Extreme Climate Conditions; Plant Health; Research and Development; Training and Information for farmers; and Leveraging positive impacts. Drawing from these programmes and the specific measures they included, the AHP aimed to prioritize adaptation options in the Guadiana River Basin. Four options were identified according to their feasibility and their relevance for the area under study, and a range of criterion were chosen. These are summarised in the hierarchy tree in Figure 1.
Figure 1. AHP hierarchy for agricultural adaptation options.
The next step was to carry out a pairwise comparison, comparing individual elements to one another, with respect to their impact or importance on an element above them in the hierarchy. Firstly, participants were asked to compare the relative preference for each of the measures with every criterion. For example, for the first criterion, feasibility of legal and political implementation (of the chosen measure), participants compared one option against another in relation to the ability of each option to be designed, supported and implemented from a legal and political standpoint. This exercise was repeated with each of the six criteria. Secondly, participants were asked to assess the relative importance of each of the criteria with respect to the achievement of the goal. i.e. they compared the relative importance of each criteria for the adaptation of the agricultural sector to climate change in the Guadiana River Basin. Answers were processed using the decision-making software Expert Choice.
The results are shown below in Figure 2.
Figure 2. Aggregate results from the AHP exercise for adaptation options.
The aggregated results show that the options Choice of new crop varieties best suited to new climate conditions and Improving technical efficiency in the use of water were equal first position in the ranking. Creation of agricultural insurance systems ranks third and finally Increase reservoir storage capacity ranks fourth. Choice of new crop varieties best suited to new climate conditions and Improving technical efficiency in the use of water performed well under all selected criteria, ranking first except for financial feasibility and speed of implementation, whereas Creation of agricultural insurance systems ranked first due to its lower cost and ease of implementation. The Increase reservoir storage capacity option was ranked low in aggregate terms and was highly controversial and criticized by most respondents, who made reference to the high cost and large environmental impact of this option.
When analysing the criteria, the protection of environmental resources was the most influential criterion at the aggregate level with a weight of 35.4%, followed by financial feasibility and capacity to generate employment. The protection of environmental resources was the dominant overall criterion given support by all respondent groups, even farmers. Similarly financial feasibility was highly ranked by most groups, especially policymakers.
The AHP analysis showed that at an aggregate level, options related to private farming (new crops and irrigation efficiency) ranked highest, public-funded ‘hard’ measures (reservoirs) ranked lowest, and public ‘soft’ measures (insurance) fell in the middle. Environmental criteria were preferred to socioeconomic and technical criteria. There were, however, differences in the ranking between groups. Whilst environmental organisations and academics ranked climate change options similarly to the average aggregate, policy makers preferred ‘soft’ measures (insurance) and discarded large irrigation infrastructures (probably due to financial, political and environmental constraints). Farmers’ priorities were technically-oriented, giving the highest ranking to the construction of water storage infrastructure.
Case
Study 2: Adaptation Options for Viticulture in Tuscany, Italy
Wine production is one of the most important, traditional economic activities for Tuscan farmers, and viticulture shapes the Tuscan hills unique landscape, which has high tourism benefits (Trombi et al. 2011). Recent wine production has moved to high-quality production, with lower yield, less chemicals and increased value, and there is an increasing number of agri-tourism farms (Trombi and Bindi, 2008). However, climate change will increase temperatures, and is considered likely to decrease precipitation and increase variability (Moriondo et al., 2011). These changes have the potential to lower yields and increase the variability of production and quality of wine (Bernetti et al., 2012; Moriondo et al. 2013). Whilst there are many potential adaptation options for preserving the quality and quantity of production, further analysis and appraisal is required to identify which options can successfully be applied to the particular context of Tuscan viticulture.
Appraising options
The goal of this AHP exercise was to identify “the best adaptation measure for Tuscan viticulture in a climate change scenario”. The analysis identified the following three adaptation options:
The “Selection” option was chosen on the basis of expert judgment, while the other two (“Relocation” and “Switch”) were chosen on the basis of a previous study (Moriondo et al., 2011).
Four criteria were used in the AHP exercise: Economical Profitability and Cost, Technical Feasibility, Social-Institutional Acceptability and Flexibility of the Measure. The selection of the criteria was based on expert judgment. The hierarchy is shown in the Figure below.
Figure 3. Hierarchy of the AHP exercise in the online tool.
A range of local stakeholders were selected and participated in the AHP exercise including technicians landscape architects, representatives from the scientific community, producers’ associations / extension services, agriculture, an environmental association and a politician / administrator. A web-based application1 was developed to allow the remote participation of the stakeholders and to increase the probability of a higher number of participants. The software reproduced the steps of the AHP method, with an animated help function to facilitate the user during the process.
Results
The stakeholders chose the Selection option as the best adaptation measure for Tuscan viticulture (0.603) by some margin, followed by Relocation (0.200) and then by the Switch (0.197) option (Table 1).
Economic profitability and costs was ranked as the most important criterion by the stakeholders, at 0.470 (Table 2) and performed well against all the other criteria (Table 3). Technical feasibility was ranked as the second most important criterion (0.262), and performed well against the Social-Institutional acceptability criterion (3.492), and slightly better than Flexibility (1.578). The Flexibility of the measure was ranked third (0.141) and was considered only slightly more important than the Social-Institutional acceptability, which was ranked as the least important criterion (0.127) in the decision process.
Table 4 shows the performance of each option against the others, under all the criteria: e.g. the Selection option performed quite well under all criteria compared to both other options. i.e. the Selection option was considered from moderately to definitively better/more important than Relocation, in particular, with respect to Flexibility, Social-institutional acceptability, and Technical feasibility (first data row of Table 4). The Selection option showed a similar performance with respect to the Switch option. The Relocation option ranked slightly better than the Switch option (second data row of Table 4). However, the Switch option was chosen once by stakeholders, when compared with Relocation, due to its slightly better Technical feasibility (red cell in third data row of Table 4). The results reveal that the most preferred option is Selection, which allows current cultivated varieties to continue and the preservation of tradition, quality and brand. It is also perceived as profitable, flexible, easy to implement and would probably incur less resistance from society than the other options.
The exercise allowed different stakeholders – who often do not often communicate with each other – to interact, and to produce a final, coherent and quantitative result, highlighting priorities for further research.
1 For more information about the web-based AHP application, please contact Giacomo Trombi (giacomo.trombi@unifi.it).
Wine production is one of the most important, traditional economic activities for Tuscan farmers, and viticulture shapes the Tuscan hills unique landscape, which has high tourism benefits (Trombi et al. 2011). Recent wine production has moved to high-quality production, with lower yield, less chemicals and increased value, and there is an increasing number of agri-tourism farms (Trombi and Bindi, 2008). However, climate change will increase temperatures, and is considered likely to decrease precipitation and increase variability (Moriondo et al., 2011). These changes have the potential to lower yields and increase the variability of production and quality of wine (Bernetti et al., 2012; Moriondo et al. 2013). Whilst there are many potential adaptation options for preserving the quality and quantity of production, further analysis and appraisal is required to identify which options can successfully be applied to the particular context of Tuscan viticulture.
Appraising options
The goal of this AHP exercise was to identify “the best adaptation measure for Tuscan viticulture in a climate change scenario”. The analysis identified the following three adaptation options:
- Selection: set up a genetic selection program in order to make the current cultivated varieties more suitable for projected climate conditions. This option was chosen based on expert judgment, and because it could help in the analysis of the preferences expressed;
- Relocation: relocation of the vineyards towards higher elevations, to reduce the impact of changes in temperature and keep cultivation in conditions similar to the present; and
- Switch: switch to other, southern varieties, more suitable for the warmer and drier conditions projected for the region.
The “Selection” option was chosen on the basis of expert judgment, while the other two (“Relocation” and “Switch”) were chosen on the basis of a previous study (Moriondo et al., 2011).
Four criteria were used in the AHP exercise: Economical Profitability and Cost, Technical Feasibility, Social-Institutional Acceptability and Flexibility of the Measure. The selection of the criteria was based on expert judgment. The hierarchy is shown in the Figure below.
Figure 3. Hierarchy of the AHP exercise in the online tool.
A range of local stakeholders were selected and participated in the AHP exercise including technicians landscape architects, representatives from the scientific community, producers’ associations / extension services, agriculture, an environmental association and a politician / administrator. A web-based application1 was developed to allow the remote participation of the stakeholders and to increase the probability of a higher number of participants. The software reproduced the steps of the AHP method, with an animated help function to facilitate the user during the process.
Results
The stakeholders chose the Selection option as the best adaptation measure for Tuscan viticulture (0.603) by some margin, followed by Relocation (0.200) and then by the Switch (0.197) option (Table 1).
Economic profitability and costs was ranked as the most important criterion by the stakeholders, at 0.470 (Table 2) and performed well against all the other criteria (Table 3). Technical feasibility was ranked as the second most important criterion (0.262), and performed well against the Social-Institutional acceptability criterion (3.492), and slightly better than Flexibility (1.578). The Flexibility of the measure was ranked third (0.141) and was considered only slightly more important than the Social-Institutional acceptability, which was ranked as the least important criterion (0.127) in the decision process.
Table 4 shows the performance of each option against the others, under all the criteria: e.g. the Selection option performed quite well under all criteria compared to both other options. i.e. the Selection option was considered from moderately to definitively better/more important than Relocation, in particular, with respect to Flexibility, Social-institutional acceptability, and Technical feasibility (first data row of Table 4). The Selection option showed a similar performance with respect to the Switch option. The Relocation option ranked slightly better than the Switch option (second data row of Table 4). However, the Switch option was chosen once by stakeholders, when compared with Relocation, due to its slightly better Technical feasibility (red cell in third data row of Table 4). The results reveal that the most preferred option is Selection, which allows current cultivated varieties to continue and the preservation of tradition, quality and brand. It is also perceived as profitable, flexible, easy to implement and would probably incur less resistance from society than the other options.
The exercise allowed different stakeholders – who often do not often communicate with each other – to interact, and to produce a final, coherent and quantitative result, highlighting priorities for further research.
1 For more information about the web-based AHP application, please contact Giacomo Trombi (giacomo.trombi@unifi.it).
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