How to answer

If knowledge on future impacts is not readily available, or alternatively, if a representative range of uncertainty has not been explored, the next relevant question for the analyst to pose is whether there are impact models available for her adaptation situation.

In the case that there are no impact models available, impact analysis must rely on methods types of trend detection and impact attribution in order to build a model, or vulnerability indication. See Table 2.1 for a summary and examples. The decision on whether to use indicators or knowledge elicitation, in the form of asking experts or stakeholders depends on several criteria, such as data availability and the skills and resources available to carrying out a study, as well as, the potential for conflict. Knowledge elicitation may be preferable when the potential for conflict is high as actors are more likely to buy into the decisions process if they are engaged early on. These methods are discussed in the respective sections on vulnerability indication and on asking experts.