Articles | Volume 17, issue 5
https://doi.org/10.5194/os-17-1321-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-17-1321-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
A dynamically based method for estimating the Atlantic meridional overturning circulation at 26° N from satellite altimetry
National Oceanography Centre, University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, UK
Eleanor Frajka-Williams
National Oceanography Centre, University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, UK
Ben I. Moat
National Oceanography Centre, University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, UK
David A. Smeed
National Oceanography Centre, University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, UK
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Jack Giddings, Karen J. Heywood, Adrian J. Matthews, Manoj M. Joshi, Benjamin G. M. Webber, Alejandra Sanchez-Franks, Brian A. King, and Puthenveettil N. Vinayachandran
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Ocean Sci., 17, 285–299, https://doi.org/10.5194/os-17-285-2021, https://doi.org/10.5194/os-17-285-2021, 2021
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The RAPID array has observed the Atlantic meridional overturning circulation (AMOC) since 2004, but the AMOC was directly calculated only five times from 1957–2004. Here we create a statistical regression model from RAPID data, relating AMOC changes to density changes within the different water masses at 26° N, and apply it to historical hydrographic data. The resulting 1981–2016 record shows that the AMOC from 2008–2012 was its weakest since the mid-1980s, but it shows no overall decline.
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Short summary
In the North Atlantic, ocean currents carry warm surface waters northward and return cooler deep waters southward. This type of ocean circulation, known as overturning, is important for the Earth’s climate. This overturning has been measured using a mooring array at 26° N in the North Atlantic since 2004. Here we use these mooring data and global satellite data to produce a new method for monitoring the overturning over longer timescales, which could potentially be applied to different latitudes.
In the North Atlantic, ocean currents carry warm surface waters northward and return cooler deep...