The need to stabilize global climate: Climate change will be the greatest threat to humanity and global ecosystems in the coming years, and there is a pressing need to understand and communicate the impacts of warming, across the perspectives of the natural and social sciences. Hoegh-Guldberg et al. review the climate change–impact literature, expanding on the recent report of the Intergovernmental Panel on Climate Change. They provide evidence of the impacts of warming at 1°, 1.5°, and 2°C—and higher—for the physical system, ecosystems, agriculture, and human livelihoods. The benefits of limiting climate change to no more than 1.5°C above preindustrial levels would outweigh the costs. Science , this issue p. eaaw6974

Across the world, policies and measures are being developed and implemented to reduce the risks of climate change and adapt to its current and projected adverse effects. The Paris Agreement established the global stocktake to evaluate the collective progress made on adaptation. Nevertheless, various challenges still exist when evaluating adaptation progress, among which is the lack of standard definitions to support evaluation efforts. Therefore, we investigated the views of experts regarding the definitions of adaptation given by the Intergovernmental Panel on Climate Change (IPCC) and the definition of successful adaptation by Doria et al., with a focus on Latin America. Using the Delphi method, we obtained relevant knowledge and perspectives. As a result, we identified a high level of consensus (85%) among the experts regarding the IPCC’s definition of climate adaptation. However, there was no consensus on the definition of successful adaptation. For both definitions, we present the elements on which the experts agreed and disagreed, as well as the proposed elements that could improve the definitions to support adaptation evaluation efforts. Additionally, we introduce a list of criteria and indicators that could improve the evaluation of adaptation at different management levels and facilitate the aggregation of information on adaptation progress.

Adaptation options are being implemented globally to reduce the impacts of current and projected climate change. However, there is still limited information on assessments of the options available, especially related to adaptation research and practice in the Global South. Therefore, we present the local feasibility assessment of climate adaptation options as a methodological advancement, using Puerto Morazán’s (Nicaragua) agriculture and livestock sectors as proof of concept. For this case study, we complement current frameworks with participatory approaches and local expert knowledge to contextualize global narratives on adaptation feasibility and overcome information availability challenges. As a result, we assess sixteen options across the agriculture and livestock sectors. We demonstrate that, depending on the context, not all dimensions and criteria are equally relevant. In Puerto Morazán, the environmental and economic dimensions were the most important. We also confirm that the assessment of the options varies when local priorities are considered. Our results highlight the importance of the local context when identifying adaptation options. Our expanded assessment framework helps assess and generate evidence from the local level, where information is usually limited. The advanced assessment can guide local and subnational adaptation processes and inform other policy or scientific assessments by identifying the dimensions where there might be barriers to implementing adaptation.