To the Editor —

Transformational change is an essential part of society's adaptive and mitigative response to climate change. Existing structures, institutions, habits and priorities need to be critically re-evaluated in light of the risks that climate change poses. Although some transformation will be forced on society as a last resort, some will be more voluntary, positive and anticipatory1,2.

The latter sort of adaptation is neglected in the recent Commentary by Dow et al.3 on limits to adaptation. Implicitly and explicitly, they present transformational change as outside rather than part of the scope of successful adaptation. Focused on determining where individual or group adaptation limits lie, they present a transformation in behaviour as a response to an 'absence of new adaptation options or resources' and a discontinuity that is 'symptomatic of an adaptation limit being reached'. But rather than a shift from adaptation to non-adaptation, the above represents a move from one major adaptation strategy to another. For example, Dow et al. present a farmer's decision to exit farming as a negative situation of 'abandonment'. But such a move may be highly rational and desirable from a personal, familial and ecological point of view, as examples in Australia suggest1,4,5. This is especially the case if it fosters public goods, such as revegetation for carbon sequestration and emissions reductions. Mitigation is a crucial part of successful adaption, and it requires transformational responses.

As is argued about other aspects of climate change6, uncertain system dynamics mean that the prediction of adaptation limits — as Dow et al. call for — is unfeasible. Adaptation is necessarily experimental. Strategic shifts are frequently going to be needed in response to new conditions and information. They will also emerge as we reassess existing trajectories and goals. Adaptation cannot simply be a conservative project of protecting things we value, at least in the developed world. Our existing values and norms need to be thoroughly re-evaluated as part of the adaptation project.

As others' have pointed out7,8, how we frame climate change adaptation strongly influences the way that people approach the issue. It is imperative that the potential for positive transformational change is included in the scope of planned adaptation options and policies.