Historical Emissions and the Carbon Budget

How should the world's remaining carbon budget be divided among countries? We assess the role of a fault‐based principle in answering this question. Discussion of the role of historical emissions in dividing the global carbon budget has tended to focus on emissions before 1990. We think that this is in part because 1990 seems so recent, and thus post‐1990 emissions seem to constitute a lesser portion of historical emissions. This point of view was undoubtedly warranted in the early 1990s, when discussion of fault‐based principles in this context began. While this view still has some intuitive force, we find that it and the associated focus on pre‐1990 emissions are now out of date. Emissions since 1990 in fact constitute a large and rapidly increasing proportion of emissions since 1750 – approximately half of the carbon emissions due to fossil fuel use and cement production, at the time of writing. We show that a restricted fault‐based principle, according to which emissions should be divided among countries on the basis of their emissions since 1990, is both viable and powerful. We consider standard objections to a fault‐based principle in this context, how such a principle might more concretely be applied, and its likely implications.     

Stress reappraisal during a mathematics competition: testing effects on cardiovascular approach-oriented states and exploring the moderating role of gender

Background and objectives: Effects of reappraising stress arousal during an interpersonal competition were tested on physiological functioning and performance. Additionally, the moderating role of gender was explored.

Design and method: Participants (N?=?279) were randomly assigned to a stress reappraisal, stress-is-debilitating, or a neutral control condition. Reappraisal materials educated participants about the adaptive benefits of stress, whereas stress-is-debilitating materials instructed participants to avoid stress. Control materials did not mention stress. Participants then competed against a gender-matched confederate on a 10-minute math performance task while cardiovascular reactivity was assessed. Participants were instructed to complete math problems as quickly and accurately as they could and were informed that a winner and loser would be determined by the resulting math scores.

Results: Reappraising stress arousal led to more adaptive challenge-like cardiovascular responses, but no condition effects were observed on math performance. Exploratory analyses revealed that reappraisal instructions were effective for improving physiological functioning and facilitating performance for men, but women were unaffected by the manipulation.

Conclusions: Reappraising stress arousal can improve physiological functioning during interpersonal competitions, but effects may be limited to men. Implications for future research are discussed.