Defining and Experiencing Dangerous Climate Change

Understanding what constitutes dangerous climate change is of critical importance for future concerted action (Schneider, 2001, 2002). To date separate scientific and policy discourses have proceeded with competing and somewhat arbitrary definitions of danger based on a variety of assumptions and assessments generally undertaken by 'experts'. We argue that it is not possible to make progress on defining dangerous climate change, or in developing sustainable responses to this global problem, without recognising the central role played by social or individual perceptions of danger. There are therefore at least two contrasting perspectives on dangerous climate change, what we term 'external' and 'internal' definitions of risk. External definitions are usually based on scientific risk analysis, performed by experts, of system characteristics of the physical or social world. Internal definitions of danger recognise that to be real, danger has to be either experienced or perceived - it is the individual or collective experience or perception of insecurity or lack of safety that constitutes the danger. A robust policy response must appreciate both external and internal definitions of danger.