This review provides an overview of the research on nonverbal expressions of positive emotions, organised into emotion families, that is, clusters sharing common characteristics. Epistemological positive emotions (amusement, relief, awe, and interest) are found to have distinct, recognisable displays via vocal or facial cues, while the agency-approach positive emotions (elation and pride) appear to be associated with recognisable visual, but not auditory, cues. Evidence is less strong for the prosocial emotions (love, compassion, gratitude, and admiration) in any modality other than touch, and there is little support for distinct recognisable signals of the savouring positive emotions (contentment, sensory pleasure, and desire). In closing, some limitations of extant work are noted and some proposals for future research are outlined.

Posed stimuli dominate the study of nonverbal communication of emotion, but concerns have been raised that the use of posed stimuli may inflate recognition accuracy relative to spontaneous expressions. Here, we compare recognition of emotions from spontaneous expressions with that of matched posed stimuli. Participants made forced-choice judgments about the expressed emotion and whether the expression was spontaneous, and rated expressions on intensity (Experiments 1 and 2) and prototypicality (Experiment 2). Listeners were able to accurately infer emotions from both posed and spontaneous expressions, from auditory, visual, and audiovisual cues. Furthermore, perceived intensity and prototypicality were found to play a role in the accurate recognition of emotion, particularly from spontaneous expressions. Our findings demonstrate that perceivers can reliably recognise emotions from spontaneous expressions, and that depending on the comparison set, recognition levels can even be equivalent to that of posed stimulus sets.

Climate change and loss of biodiversity are advancing rapidly, making a transition to a more sustainable society one of the most pressing tasks facing humanity. This special section shines a spotlight on how emotions shape and are shaped by the climate and biodiversity crises, and how they intersect with pro-environmental behavior. To this end, leading sustainability scholars and policy makers articulate what they believe are the most important questions that emotion research should answer to support a sustainable societal transition. Here, we first provide an overview of the articles in the special section, which include a wide range of topics including global analyses of distress related to climate change and biodiversity loss, case studies on emotional experiences toward locally specific instances of climate change consequences and adaptation or mitigation efforts, discussions of the motivational functions of emotions and their potential to drive pro-environmental action, and reflections on how we can make affective science more salient to policy makers in the sustainability domain. In the second part, we summarize the emerging overarching themes that point to promising research objectives and questions for affective sustainability science. Finally, we discuss how the study of sustainability can also be beneficial for the affective sciences. Our hope is that this special section will put sustainability on the research agenda of emotion researchers and stimulate more research in affective sustainability science.