Quantifying generational and geographical inequality of climate change.

We relate greenhouse gas emissions and global warming experienced over a lifetime by individual birth cohorts, resolved by world regions. We reveal outstanding geographical inequality between high- and low-emission regions corresponding to the nations of the Global North and Global South, respectively. Additionally, we highlight the inequality different birth cohorts (generations) experience regarding the burden of recent and ongoing warming temperatures as a time-delayed consequence of past emissions. We achieve precise quantification of the number of birth cohorts and populations who see a difference between Shared Socioeconomic Pathways (SSPs), emphasizing the potential for action and the chances for improvement that exist under the different scenarios. The method is designed to realistically display inequality, as it is experienced by people while motivating action and change needed to achieve emission reduction to reduce climate change and generational and geographical inequality simultaneously.

Large uncertainties in trends of energy demand for heating and cooling under climate change.

The energy demand for heating and cooling buildings is changing with global warming. Using proxies of climate-driven energy demand based on the heating and cooling Degree-Days methodology applied to thirty global climate model simulations, we show that, over all continental areas, the climate-driven energy demand trends for heating and cooling were weak, changing by less than 10% from 1950 to 1990, but become stronger from 1990 to 2030, changing by more than 10%. With the multi-model mean, the increasing trends in cooling energy demand are more pronounced than the decreasing trends in heating. The changes in cooling, however, are highly variable depending on individual simulations, ranging from a few to several hundred percent in most of the densely populated mid-latitude areas. This work presents an example of the challenges that accompany future energy demand quantification as a result of the uncertainty in the projected climate.

History meets palaeoscience: Consilience and collaboration in studying past societal responses to environmental change.

History and archaeology have a well-established engagement with issues of premodern societal development and the interaction between physical and cultural environments; together, they offer a holistic view that can generate insights into the nature of cultural resilience and adaptation, as well as responses to catastrophe. Grasping the challenges that climate change presents and evolving appropriate policies that promote and support mitigation and adaptation requires not only an understanding of the science and the contemporary politics, but also an understanding of the history of the societies affected and in particular of their cultural logic. But whereas archaeologists have developed productive links with the paleosciences, historians have, on the whole, remained muted voices in the debate until recently. Here, we suggest several ways in which a consilience between the historical sciences and the natural sciences, including attention to even distant historical pasts, can deepen contemporary understanding of environmental change and its effects on human societies.