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Some definitions for adaptation methods

One way which may help in determining which methods to use to support ADM is to consider the multiple possible dimensions of a method that can be used to provide a classification of methods.
Frameworks for decision-making image

One way which may help in determining which method or methods to use to support adaptation decision-making is to consider the multiple possible dimensions of a method, tool or process that can be used to provide a basic classification of methods. Some of the important dimensions are a matter of degree whereas others are of a mutually exclusive nature. Some of the important choices are, for example:

  • participatory or expert-based methods …
  • computerised or not …
  • black box or transparent …
  • local or wider-scale …
  • formal or informal …

More well-structured classifications of CCVIA methods are of course available, eg the IPCC classification (Carter et al. 2007) and the UNFCCC compendium (2005), and work is proceding on the development of new typologies with an increasing focus on adaptation (we encourage readers to have a look at the outputs of the Mediation project which is addressing this particular need). However these works presume the reader is familiar with a number of related approaches in assessment and modelling. In contrast, the following definitions provide a first order characterisation of methods based on information that can, in most cases, be easily obtained:

Formal methods:

Formal methods involve the use of well-structured decision-making processes and introduces a level of rigour that allows confidence in any comparisons. They are usually tried and tested in many other situations, are familiar to many stakeholders, and especially popular among academics and analysts. Eg CBA.

Informal methods:

Unstructured decision support activity can allow creative thinking and improved flow of discussion for example. Minimal guidance is provided in principle, and could require that an experienced facilitator is present. It does not need all participants to agree on a particular rating/ranking. It can include different views and possible conflicts. Eg. Pros and Cons..

Expert methods:

Expert methods are undertaken by ‘analyst’ with high level of training and methodical knowledge. A study is consistent with theoretical background and principles – clearly this can be a mixed blessing. Professional standards ensures good documentation of the process, and also lends a certain ‘authority’ to the result.

Participatory methods:

This type of method usually involves different stakeholders and therefore different types of knowledge. Results could have a greater ‘legitimacy’ for some audiences. ‘Expert methods’ above is different from ‘expert judgement’ and relates to analytic expertise whereas the latter could include wide participation and different type of expertise eg. local or cultural knowledge. Eg. voting or ranking methods including participatory MCA.

The methods mentioned in relation to the above definitions (as well as many other methods) can be explored further starting from the knowledgebase article listing suggested decision methods.

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Carter, T.R., R.N. Jones, X. Lu, S. Bhadwal, C. Conde, L.O. Mearns, B.C. O’Neill, M.D.A. Rounsevell and M.B. Zurek, 2007. New Assessment Methods and the Characterisation of Future Conditions. 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, 133-171

UNFCCC 2005. Compendium on methods and tools to evaluate impacts of, vulnerability and adaptation to, global environmental change. Available online at:

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