Identifying Future Climate Impacts

Abrupt climate changes as well as steady changes that cross thresholds can have rapid impacts on human infrastructure and ecosystems, according to a National Research Council report. The report assesses which climate-change threats are expected to be abrupt—that is, occurring over a few years or decades—and which ones are unlikely to occur this century. For example, the report finds that abrupt changes include the disappearance of late-summer Arctic sea ice and increases in extinction rates of marine and terrestrial species. The report also notes that steady climate changes can cause abrupt changes if they cross a threshold—such as rising sea levels that exceed current sea wall heights. The report recommends that an abrupt-change early-warning system be developed to help anticipate future abrupt changes and reduce their impacts.