MOSAiC

Arctic climate change is amplified relative to global change and is embodied by a dramatic decline in the perennial sea-ice pack. These cryospheric transitions carry significant implications for regional resource development, geopolitics, and global climate patterns. Indeed the changing Arctic cryosphere is considered a grand challenge for global climate research. Arctic change, and its linkages with the global system, must be understood. In addition, there is a growing stakeholder community that expects improved sea-ice forecasting for many applications. To make progress on these important issues requires developing a detailed, process-level understanding of the coupled climate system that can help to address the numerous deficiencies in numerical model representations of the Arctic. Such an understanding is only possible by making targeted, interdisciplinary measurements within the central Arctic sea ice environment. The Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC) initiative has been developed in response to these great challenges. It is comprised of three parts:

1. An intensive, icebreaker-based observatory that will freeze in, and drift with, the Arctic sea ice for a full annual cycle making interdisciplinary measurements in the atmosphere, sea ice, upper ocean, and biosphere.
2. A distributed network of targeted, autonomous measurements to characterize spatial variability on model grid-box scales
3. Coordinated, multiscale analysis and modeling activities.

MOSAiC is a major, international effort that will require the modular participation of many different agencies and entities. DOE ARM user facility is uniquely positioned to play a critical role in this initiative by providing a comprehensive instrument suite to characterize the atmosphere and its interactions with the sea-ice surface. In support of MOSAIC, ARM will operate its second ARM Mobile Facility (AMF2) and Mobile Aerosol Observing System at the central observatory as it drifts through the central Arctic for a 13-14-month campaign starting in September 2019. Sea ice is an integrator of energy fluxes in the coupled Arctic climate system; thus, atmosphere-ice-ocean processes impacting the flow of energy through this system in all seasons are the primary target of MOSAIC. The broader, collaborative MOSAIC initiative will allow for many inter-disciplinary studies along this theme. ARM’s involvement will target specific areas related to the atmosphere and atmosphere-surface interactions that are critically under-observed in the Arctic, are leading contributors to model uncertainties in the region, and are programmatically important to DOE research and modeling programs. The guiding science themes for this project include:

1. Surface energy budget of sea ice
2. Clouds and precipitation
3. Aerosols
4. Atmospheric boundary layer

Many fundamental issues concerning these themes are lacking in observational constraints, particularly in the Arctic winter and through consecutive seasons. For example, little is known about the energy budget of first-year sea ice, the annual cycle of central Arctic aerosol concentrations, the spatial organization of cloud-precipitation systems relative to sea-ice heterogeneity, the winter boundary layer evolution, or cloud-surface coupling processes over sea ice. The proposed ARM observations will be ground-breaking in many ways and will ultimately have a dramatic impact on the Arctic research community and its ability to represent coupled Arctic processes in numerical models.

Timeline

Campaign Data Sets

MOS Data Sources