Delivering Sustained, Coordinated, and Integrated Observations of the Southern Ocean for Global Impact

Louise Newman,Gunnar Spreen,Oscar Schofield,Joana Beja,Ted Maksym,Patricia Miloslavich,Richard Coleman,Inga J Smith,Katharine R Hendry,Sarah T Gille,Robert A Massom,Stefan Kern,Sebastiaan Swart,Robin Robertson,Rowan Trebilco,Katsuro Katsumata,Esmee Van Wijk,Jiuxin Shi,Riccardo Farneti,Jess Melbourne-Thomas ,Andrew J S Meijers ,Jan L Lieser ,Daniel P Costa ,Sian F Henley ,Irene R Schloss ,Andrew J Constable ,Eileen E Hofmann ,Guy D Williams ,Michael P Meredith ,Elisabeth L Sikes ,Burcu Özsoy ,Stephen Diggs ,Michael Williams ,P Bricher ,Sébastien Moreau ,Sarah E Fawcett ,Laura Herráiz‐Borreguero ,Anna Wåhlin ,Matthew R Mazloff ,P̀etra Heil ,Karen M Assmann

doi:10.3389/fmars.2019.00433

Abstract

The Southern Ocean is disproportionately important in its effect on the Earth system, impacting climatic, biogeochemical and ecological systems, which makes recent observed changes to this system cause for global concern. The enhanced understanding and improvements in predictive skill needed for understanding and projecting future states of the Southern Ocean require sustained observations. Over the last decade, the Southern Ocean Observing System (SOOS) has established networks for enhancing regional coordination and research community groups to advance development of observing system capabilities. These networks support delivery of the SOOS 20-year vision, which is to develop a circumpolar system that ensures time series of key variables, and deliver the greatest impact from data to all key end-users. Although the Southern Ocean remains one of the least-observed ocean regions, enhanced international coordination and advances in autonomous platforms have resulted in progress towards addressing the need for sustained observations of this region. Since 2009, the Southern Ocean community has deployed over 5700 observational platforms south of 40°S. Large-scale, multi-year or sustained, multidisciplinary efforts have been supported and are now delivering observations of essential variables at space and time scales that enable assessment of changes being observed in Southern Ocean systems. The improved observational coverage, however, is predominantly for the open ocean, encompasses the summer, consists of primarily physical oceanographic variables and covers surface to 2000 m. Significant gaps remain in observations of the ice-impacted ocean, the sea ice, depths more than 2000 m, the air-sea-ice interface, biogeochemical and biological variables, and for seasons other than summer. Addressing these data gaps in a sustained way requires parallel advances in coordination networks, cyberinfrastructure and data management tools, observational platform and sensor technology, platform interrogation and data-transmission technologies, modeling frameworks, and internationally agreed sampling requirements of key variables. This paper presents a community statement on the major scientific and observational progress of the last decade, and importantly, an assessment of key priorities for the coming decade, towards achieving the SOOS vision and delivering essential data to all end users.

Highlights

Reviewed by: Frank Dehairs, Vrije Universiteit Brussel, Belgium Mathieu Ardyna, Stanford University, United States Matthew Long, National Center for Atmospheric Research (UCAR), United States
The Southern Ocean remains poorly observed leading to uncertainty in estimates of future states of Southern Ocean processes and the consequences for the Earth system
Distilled into eight key issues, these are identified as the major data bottlenecks in addressing the Southern Ocean Observing System (SOOS) Science Themes that have underpinned the focus of SOOS networks and efforts far

Summary

Introduction

Reviewed by: Frank Dehairs, Vrije Universiteit Brussel, Belgium Mathieu Ardyna, Stanford University, United States Matthew Long, National Center for Atmospheric Research (UCAR), United States. Taking into account the progress of the community in delivering knowledge relevant to those themes (sections “Themes 1 and 2: The Role of the Southern Ocean in the Planet’s Heat and Freshwater Balance; and the Stability of the Southern Ocean Overturning Circulation,” “Theme 3: The Role of the Ocean in the Stability of the Antarctic Ice Sheet and Its Future Contribution to Sea-Level Rise,” “Theme 4: The Future and Consequences of Southern Ocean Carbon Uptake,” “Theme 5: The Future of Antarctic Sea Ice,” and “Theme 6: Impacts of Global Change on Southern Ocean Ecosystems”), the Southern Ocean community has identified eight key issues of focus for the coming decade.

Results

Conclusion