讲座内容：

Climate change is one of the most urgent problems facing the earth. Its facets are multiple: environmental, economic, and social, and its consequences could become dire if drastic and concerted action is not taken immediately. Climate change is already exerting a host of stresses on the environment and the society that will intensify with time. In the face of this reality, humanity has done little to avert possible catastrophes. Puzzling as this behavior might appear at first, it can be partially explained by behavioral economics and psychology. The goal of this talk is twofold. First, it investigates the question of whether the UN goal of 2 °C temperature rise above preindustrial level is still attainable in an optimal sense and what reductions are needed to achieve it. Second, the talk makes a connection between such reductions and certain behavioral aspects that could make the reductions a reality. These two goals might appear technically distinct and to some extent they are. However, there exists a strong cause-and-effect connection between the two since sharp emissions reductions require strong political consensus on the part of politicians, decision makers, and citizens that hinge upon human behavior.

A climate model is used in conjunction with an economic model to examine emissions and temperature dynamics under certain economic growth scenarios. Consumption, carbon emissions, and resulting temperature trajectories are then optimized so that a utility function is maximized with the goal of keeping temperature rise within 2 °C above preindustrial levels. Two measures of satisfaction from consumption are considered: a logarithmic utility and a novel, hump-shaped function. The latter is consistent with recent findings about the relation between life satisfaction and income. A meta-analysis follows that links the optimal emissions trajectories with corresponding behavioral requirements. Thus, climate action is presented in a more integral way whereby technical and behavioral attributes are systematically connected. It is demonstrated that:

• the 2 °C target is theoretically still achievable but it hinges upon very drastic measures to be taken almost immediately

• in a few years we shall exit the 2-degree controllability region and higher temperatures should be expected

• public cognition of and attitude towards climate change should change in a quantifiable sense

• this is one of those interdisciplinary problems that need not only hard science and technology to be resolved but also psychology, the humanities and an informed citizenry.