The Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) is an international Arctic research initiative aiming a one year drift experiment from October 2019 to October 2020 with the research ice breaker Polarstern of the Alfred Wegener Institute for Polar and Marine Research (AWI).
Year-round, detailed, and comprehensive measurements, extending from the atmosphere through the sea-ice and into the ocean of the central Arctic Basin are needed to improve our understanding and modeling of Arctic climate and weather, and enhance Arctic sea-ice predictive capabilities. These observations will be designed to provide a process-level understanding of the present-day central Arctic coupled climate system, consisting of dramatically less and thinner sea-ice than in the recent past, as well as a more detailed understanding of the processes leading to these sea-ice changes. Scientific emphasis will be placed on processes that transfer heat, moisture, density, and momentum through the system. To obtain the needed measurements, a manned, transpolar drifting observatory is proposed, wherein an ice-hardened ship serves as a central hub for intensive observations of atmospheric, oceanic, sea-ice, and biogeochemical properties over a full annual cycle. The comprehensive information from this central facility will be expanded to larger spatial scales using a coordinated network of distributed measurements made using buoys, unmanned aerial systems, autonomous underwater vehicles, additional ships, aircraft, and satellites. A broad consortium of nations and funding agencies is needed to facilitate, coordinate, and support such a constellation of central Arctic observations.