The Arctic Is Now Warming Four Times As Fast As the Rest of the Globe

Human activity is changing the climate system at a geologically unprecedented rate, primarily by increasing net radiative forcing as a consequence of industrial activities. Fundamental theory, observations, modeling, and paleoclimate indicate these rapid climatic changes will be more pronounced in the Arctic. At first glance, how rapidly the Arctic is heating up would appear to be a straightforward observational question. However, a number of factors identified in climate science and other environmental fields may contribute to a widespread misperception of the actual warming rate. These factors can be technical as well as sociological. Period of study, latitudinal definitions, and observational spatial coverage are examples of the former, while time lags in translating research to knowledge, information obsolescence, and a bias towards overly conservative descriptions of climatic challenges are examples of the latter. Using spatially-complete instrumental temperature records, we re-examine the rate of Arctic warming under multiple definitions. We demonstrate the Arctic is likely warming over 4 times faster than the rest of the world, some 3-4 times the global average, with higher rates found both for more recent intervals as well as more accurate latitudinal boundaries. These results stand in contrast to the widely-held conventional wisdom prevalent across scientific and lay publications alike that the Arctic is "only" warming around twice as fast as the global mean. Our findings update and re-emphasize the significance of Arctic warming in the context of extreme anthropogenic environmental disruption. Current and future changes in the Arctic have profound implications for the physical climate system, human populations and ecosystems, as well as geopolitical decision-making for commerce and global security. It is essential that the scientific community not only accurately understand but also convey the scale of Arctic warming, which is occurring nearly twice as rapidly as commonly described.