Many factors contribute to variability in Earth’s climate on a range of timescales, from seasons to decades. Natural climate variability arises from two different sources: (1) internal variability from interactions among components of the climate system, for example, between the ocean and the atmosphere, and (2) natural external forcings, such as variations in the amount of radiation from the Sun. External forcings on the climate system also arise from some human activities, such as the emission of greenhouse gases (GHGs) and aerosols. The climate that we experience is a combination of all of these factors.
Understanding climate variability on the decadal timescale is important to decision-making. Planners and policy makers want information about decadal variability in order to make decisions in a range of sectors, including for infrastructure, water resources, agriculture, and energy.
In September 2015, the National Academies of Sciences, Engineering, and Medicine convened a workshop to examine variability in Earth’s climate on decadal timescales, defined as 10 to 30 years. During the workshop, ocean and climate scientists reviewed the state of the science of decadal climate variability and its relationship to rates of human-caused global warming, and they explored opportunities for improvement in modeling and observations and assessing knowledge gaps. Frontiers in Decadal Climate Variability summarizes the presentations and discussions from the workshop.
Characterizing Risk in Climate Change Assessments:
Proceedings of a Workshop for the U.S. Global Change Research Program
The U.S. Global Change Research Program (USGCRP), in response to its legislative mandate, conducts periodic National Climate Assessments (NCA) to inform the nation about observed changes in climate, the current status of the climate, and anticipated trends for the future. The USGCRP has conducted three such assessments and intends to develop a sustained assessment process.
This workshop was designed to address a key issue for NCAs: providing information about climate-related hazards, risks, and opportunities in formats that are understandable, credible, and useful to decision makers in their efforts to reduce greenhouse gas emissions and to reduce vulnerability and increase resilience to climate change in the regions or sectors for which they are responsible.