TY - JOUR T1 - Sustainable observations of the AMOC: Methodology and Technology A1 - McCarthy,G.D. A1 - Brown,P.J. A1 - Flagg,C.N. A1 - Goni,G. A1 - Houpert,L. A1 - Hughes,C.W. A1 - Hummels,R. A1 - Inall,M. A1 - Jochumsen,K. A1 - Larsen,K.M.H. A1 - Lherminier,Pascale A1 - Meinen,C.S. A1 - Moat,B.I. A1 - Rayner,D. A1 - Rhein,M. A1 - Roessler,A. A1 - Schmid,C. A1 - Smeed,D.A. AD - ICARUS, Department of Geography Maynooth University ,Ireland AD - National Oceanography Centre Southampton, UK AD - Marine Science Research Center Stony Brook University New York ,USA AD - Atlantic Oceanographic and Meteorological Miami FL ,USA AD - Scottish Association for Marine Science Scotland, UK AD - University of Liverpool England, UK AD - National Oceanography Centre Liverpool, UK AD - GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel ,Germany AD - Federal Maritime and Hydrographic Agency Hamburg, Germany AD - Faroe Marine Research Institute, Faroe Islands AD - Ifremer, Univ. Brest, CNRS, IRD, LOPS, IUEM Plouzané, France AD - Institute for Environmental Physics Bremen University ,Germany AD - Center for Marine Environmental Sciences MARUM Bremen University ,Germany UR - https://archimer.ifremer.fr/doc/00595/70674/ DO - 10.1029/2019RG000654 KW - Ocean Observing KW - AMOC KW - Ocean Circulation N2 - The Atlantic Meridional Overturning Circulation (AMOC) is a key mechanism of heat, freshwater, and carbon redistribution in the climate system. The precept that the AMOC has changed abruptly in the past, notably during and at the end of the last ice age, and that it is ‘very likely’ to weaken in the coming century due to anthropogenic climate change is a key motivation for sustained observations of the AMOC. This paper reviews the methodology and technology used to observe the AMOC and assesses these ideas and systems for accuracy, shortcomings, potential improvements and sustainability. We review hydrographic techniques and look at how these traditional techniques can meet modern requirements. Transport mooring arrays provide the ‘gold standard’ for sustained AMOC observing, utilizing dynamic height, current meter, and other instrumentation and techniques to produce continuous observations of the AMOC. We consider the principle of these systems and how they can be sustained and improved into the future. Techniques utilizing indirect measurements, such as satellite altimetry, coupled with in‐situ measurements, such as the Argo float array, are also discussed. Existing technologies that perhaps have not been fully exploited for estimating AMOC are reviewed and considered for this purpose. Technology is constantly evolving and we look to the future of technology and how it can be deployed for sustained and expanded AMOC measurements. Finally, all of these methodologies and technologies are considered with a view to a sustained and sustainable future for AMOC observation. Plain Language Summary The Atlantic Meridional Overturning Circulation (AMOC) is a system of ocean currents (sometimes known as the Gulf Stream System or the Great Ocean Conveyor Belt) that is important because of how it moves heat and carbon around the planet. Due to human‐induced climate change, the AMOC is predicted to weaken substantially, with adverse impacts for regions dependent on the supply of warmth from the AMOC, including northwest Europe. Surprisingly, given its importance, the AMOC has only been directly measured for the last decade or so. We now have observation systems in place that can verify a future decline in the AMOC, if it happens. In this paper we review these observation systems in terms of the technology and methodology used. We look at how these systems might develop in the future, including covering any gaps that might exist. And consider how they might fit in an integrated and optimized Atlantic observing system. Y1 - 2020/03 PB - American Geophysical Union (AGU) JF - Reviews Of Geophysics SN - 8755-1209 VL - 58 IS - 1 ID - 70674 ER -