This short report summarizes climate risks and their consequences for people, food and water security, as well as national and international security, migration, economies and trade, focusing on impacts that are likely to be locked in for the period 2040–50 unless emissions drastically decline before 2030. The paper highlights the risks and likely impacts if the goals set under the Paris Agreement are not met, and the world follows an emissions pathway consistent with recent historical trends. The research paper is intended to inform briefing officials while the summary report is intended for heads of government and ministers.
According to the paper cascading climate impacts can be expected to cause higher mortality rates, drive political instability and greater national insecurity, and fuel regional and international conflict. During an expert elicitation exercise conducted as part of the research for this paper, the cascading risks that participants identified greatest concern over were the interconnections between shifting weather patterns, resulting in changes to ecosystems and the rise of pests and diseases. Combined with heatwaves and drought, these impacts will likely drive unprecedented crop failure, food insecurity and migration. In turn, all will likely result in increased infectious diseases, and a negative feedback loop compounding each impact.