Special Feature: The Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC)
Coupled processes and feedbacks in the Central Arctic
The Arctic is in a state of transition, with amplified warming, thinning sea ice, emergent processes, and wide-reaching impacts. Models are challenged to represent these changes. The international Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition of 2019-2020 used a coupled system approach to examine the processes and feedbacks that lead to the amplification of climate warming in the Arctic, the diminished Arctic sea ice, and their implications on weather, global climate, ecosystems, and model predictions. MOSAiC entailed freezing the icebreaker Polarstern, and an extensive collection of observational assets, into the Central Arctic ice pack for a full year to drift with the sea ice. Over this year, detailed observations of the atmosphere, seaice, snow, and ocean targeted physical, chemical, and biological processes. This Special Feature examines results from the MOSAiC expedition, including both individual components of the complex Central Arctic system and interdisciplinary research that cuts across multiple components. It draws upon a comprehensive suite of observations and samples, including in situ, aerial, and remote-sensing measurements, and a host of related modeling and synthesis activities. Lastly, it places MOSAiC within the context of other campaigns and analyses across the Arctic.