International efforts for a more sustainable society have often resorted to formal agreements.But these commitments are more effective if people, communities and institutions integrate them as relevant behavioural standards, or social norms. In this paper we propose to analyse how social norms are internalized as personal norms and environmental identity, and then how able they are to predict recycling and organic foods purchase behaviour in two countries -Portugal and Brazil. The role of group identification is also analysed. Results show that behaviours are better predicted by personal norms and environmental identity than by more external social norms. Moreover, the influence of social norms on personal norms and environmental identity is in part moderated by group identification: Injunctive norms predict personal norms and environmental identity better when participants are more identified with the group, while descriptive norms predict them more directly.

The role carbon emissions play in contributing to climate change makes clear the necessity for a global reconsideration of current modes of energy production. In recent years, as concerns over the threats of climate change (CC) have become more acute, four technologies have notably risen to the forefront of academic and public discourse: nuclear power, carbon capture and storage (CCS), wind power, and geoengineering. The particular interest of these four approaches lies in the fact that they reflect both energy production and climate control technologies, are often socially controversial, and present complex challenges of governance. Nuclear and wind power both deserve an important place among the variety of low‐carbon energy options. In countries where public acceptance is evaluated, although, support for nuclear energy appears to be conditional upon simultaneous development of other renewable energies alongside a feasible plan to address the disposal of nuclear waste. The Fukushima accident sharply increased public concern about the safety and vulnerability of nuclear reactors. While wind power receives general public support, issues of accommodation can arise when it comes to siting wind farms. Persistent dependency upon carbon‐producing energy has made favorable the option of CCS. However, in addition to technical and geological factors, social resistance to the placement of carbon storage units remains a key obstacle. Geoengineering offers the technological capacity to directly act on the climate should levels of atmospheric CO2 become dangerously high. Public perception regarding the risk of climate change can be labile, and the alternatives reviewed here share the characteristic that their technical and political dimensions are intertwined. The variety of options for combining and implementing these technologies, coupled with the inherently time‐sensitive nature of CC, underscore the complexity of the endeavor. In order to bridge these various levels of analysis and decision making, and to better understand and integrate people's involvement, exercises in risk governance could be developed at both the national and international levels. WIREs Clim Change 2011 2 712–727 DOI: 10.1002/wcc.134This article is categorized under: Perceptions, Behavior, and Communication of Climate Change > Social Amplification/Attenuation of Climate Risks The Carbon Economy and Climate Mitigation > Policies, Instruments, Lifestyles, Behavior