The term tipping point has been used to describe elements of the Earth system that might, in the face of changing climate, behave non-linearly, irreversibly, or both. This study will address the likelihood of various physical components of the Earth system to undergo major and rapid changes (i.e., abrupt climate change) and, as time allows, examine some of the most important potential associated impacts and risks. This study will explore how to monitor climate change for warnings of abrupt changes and emerging impacts and examine gaps in our current scientific understanding and monitoring capabilities.
Over the past several decades, scientists have come to understand that Earth’s climate is capable of large and sudden changes. A 2002 National Research Council (NRC) report entitled "Abrupt Climate Change: Inevitable Surprises" examined the state of the science of abrupt climate change. More than a decade later, a new NRC committee was commissioned to summarize the state of knowledge of the likelihood of various physical components of the Earth system to undergo major and rapid changes (i.e., abrupt climate change) and, examine some of the most important potential associated impacts and risks. This study was designed to explore how to monitor climate change for warnings of abrupt changes and emerging impacts. To gather input from the wider scientific community, the NRC committee organized four meetings interacting with more than a dozen experts in the field. The committee’s final product was a report entitled "Abrupt Impacts of Climate Change: Anticipating Surprises," which was peer-reviewed by 12 experts outside of the report committee. As the report describes, both abrupt changes in the physical climate system and steady changes in climate that can trigger abrupt changes in other physical, biological, and human systems present possible threats to nature and society. Abrupt change is already underway in some systems, and large scientific uncertainties about the likelihood of other abrupt changes highlight the need for further research. However, with recent advances in understanding of the climate system, some potential abrupt changes once thought to be imminent threats are now considered unlikely to occur this century. This report summarizes the current state of knowledge on potential abrupt changes to the ocean, atmosphere, ecosystems, and high latitude areas, and identifies key research and monitoring needs. The report calls for action to develop an abrupt change early warning system to help anticipate future abrupt changes and reduce their impacts The report can be found here: http://nas-sites.org/americasclimatechoices/other-reports-on-climate-change/2013-2/abrupt-impacts-of-climate-change/ The website includes a listing of key findings, a report in brief, a press release, a slideshow, a briefing power point, a poster presentation on the report, a short video summary featuring the Committee Chair (Jim White), and a recording of a webinar given by the committee chair and key committee members. Overall, the broader impact of the work of the National Research Council is to ensure that the best possible science is available in the public policy arena. Recommendations in NRC reports help to steer public policy, government programs, and academic institutions. It is the intent that this Committee's report be used in this same way as well as contributes to the Nation's understanding of the potential threats to nature and society posed by abrupt changes in the physical climate system and steady changes in climate that can trigger abrupt changes in other physical, biological, and human systems.
