AMOC Time Series

This website lists available AMOC time series of transports and fluxes derived from instrument arrays. While the quality-controlled raw data collected from the individual instruments is commonly submitted to data repositories such as OceanSites or the World Ocean Data Base, there is no collection site for AMOC time series products. These products require substantial post-processing that may differ depending on the instrument array configuration (e.g., types of instruments, spatial and temporal coverage of the instruments). Here we provide a short overview of available time series of interest to the AMOC community with links to either the time series itself or the project website.


(The following projects receive partial funding from US funding agencies. The projects are organized geographically from North to South.)

OSNAP(Overturning in the Subpolar North Atlantic Program)

The OSNAP moored array was deployed in 2014 and will be fully recovered for the first time in 2016. Data collected include transport, heat, and freshwater flux estimates from the Labrador (Canada) to Greenland array and the Greenland to Scotland array. Participating institutions: Duke University (USA), Rosenstiel School of Marine and Atmospheric Science, University of Miami (USA), Woods Hole Oceanographic Institution (USA), National Oceanography Center (UK), Scottish Association for Marine Sciences (UK), Oxford University (UK), University of Liverpool (UK), Bedford Institute of Oceanography (Canada), Memorial University (Canada), Ocean University of China (China), IFREMER (France), IFM-GEOMAR (Germany), Royal Netherlands Institute for Sea Research (Netherlands).

Record: Expected delivery of the first OSNAP products is late summer 2017
Sampling: Monthly
Uncertainty estimates available: Yes

 

Line W

Data collected are analyzed to derive transport estimates of the Deep Western Boundary Current over the continental slope southeast of New England. The moored array time series, started in 2004 and completed in 2014, was maintained by the Woods Hole Oceanographic Institution (USA), with water property observations collected by investigators from Lamont-Doherty Earth Observatory (USA), Bedford Institute of Oceanography (Canada) and WHOI.

Record: May-01-2004 to May-02-2014
Sampling: Variable (depending on sensor and parameter: moored sensors typically logged at 15-30 minute interval; shipboard sampling done 1-2 times per year) 
Uncertainty estimates available: Yes (in most cases) 

 

RAPID-MOCHA (Meridional Overturning Circulation and Heatflux Array)

Data include transport and heat flux estimates from the moored array at 26˚N that started in 2004 together with the long-term cable observations. This project is a collaboration between the University of Miami’s Rosenstiel School of Marine and Atmospheric Sciences (USA), the National Oceanic and Atmospheric Administration–Atlantic Oceanographic and Meteorological Laboratory (USA), and the National Oceanography Centre (UK). The RAPID-AMOC website has the merged AMOC time series data.

Record: Apr-02-2004 to Mar-22-2014  (ongoing – updates posted roughly every 18 months)
Sampling: 12-hours
Uncertainty estimates available: Yes (in publications only, not in web data file)

 

Florida Current and WBTS (Western Boundary Time Series)

Data include transport estimated of the Florida Current from the submarine cable voltage (since 1982) and calibration cruises (since 1982). Deep Western Boundary Current estimates are from moored pressure-equipped inverted echo sounders (since 2004). These time series are maintained by NOAA AOML as part of the Western Boundary Time Series project. Florida Current data are available on the project web page and DWBC data are available upon request (Christopher.Meinen@noaa.gov). 

Florida Current:

Record: Mar-18-1982 to present (updated daily with a 3-day delay)
Sampling:  Daily (cable time series) and snapshots for calibration cruises
Uncertainty estimates available: Yes (in publications only, not in web data files)

DWBC:

Record: Oct-03-2004 to Sept-27-2008 (updated sporadically)
Sampling:  Daily
Uncertainty estimates available: Yes (in publications only, not in web data files)

 

MOVE (Meridional Overturning Variability Experiment)

MOVE observes the cold deep branch of the AMOC as it passes southward east of the Caribbean, crossing a section between Guadeloupe and the Mid-Atlantic Ridge. Data include transport estimates from dynamic height moorings, bottom pressure sensors, and current meters at approximately 16˚N. This time series started as a German project in 2000 and is now maintained by the Scripps Institution of Oceanography (USA), with funding from the NOAA Climate Observations Division.

Record: Jan-2000 to present
Sampling:  Instruments typically bi-hourly or faster; transport calculations include low-pass filters with optional cut-offs between 1 and 120 days
Uncertainty estimates available: Yes (in publications)

 

SAMOC/SAMBA(South Atlantic Meridional Overturning Circulation/SAMoc Basin-wide Array)

A trans-basin array of tall moorings, pressure-equipped inverted echo sounders, and current meters at 34.5˚S. Parts of the array have been in place since 2009; the full array has been in place since 2014. Participating institutions include: Department of Environmental Affairs (South Africa), Ecole Normale Superieure, Laboratoire de Meteorologie Dynamique (France), Laboratoire de Physique des Oceans – IFREMER (France), NOAA Atlantic Oceanographic and Meteorological Laboratory (USA), Servicio de Hidrografia Naval (Argentina), Universidad de Buenos Aires (Argentina), Universidade de Sao Paulo (Brazil), University of Cape Town (South Africa), and the University of Miami/CIMAS (USA). NOAA AOML maintains time series of western boundary data collected by the US here. AMOC estimates generated from ~6 years of data (~20 months in 2009-2010, ~4 years in 2013-2017) along 34.5˚S are available at the SAMOC International webpage

Record: Mar-18-2009 to present (updated sporadically after recovery cruises ~ once per year)
Sampling:  Daily, Seasonal Cycle, Interannual Anomalies
Uncertainty estimates available: Yes (in web data files)

 

 

(The following projects provide time series of interest to the AMOC community but are supported internationally.)

Regional Atlantic Circulation and Global Change (RACE)

RACE is a project funded by Germany through BMBF-Verbundvorhaben for climate research in the ocean. RACE WP1.1 involves the collection of current and hydrographic measurements of the western boundary current system along 5°S and 11°S using a mooring array and ship based observations. The observed variability of the western boundary current system will be related to the variability of the AMOC at the deep-water formation sites of the North Atlantic as well as the Agulhas region concerning the signal propagation within the AMOC. Furthermore, possible connections between the new transport time series of the North Brazil Undercurrent (NBUC) and the transport variability of the Equatorial Undercurrent (EUC) as well as the resulting consequences for the climate relevant surface temperatures of the equatorial East Atlantic will be analyzed. The current array is maintained since 2013 by GEOMAR, Helmholtz-Zentrum fur Ozeanforschung Kiel, but a former array at the same location provided timeseries data from March 2000 to August 2004.

Record: Jul-07-2013 to Oct-03-2015
Sampling: Instruments of the array sample at 2-hour resolution.
Uncertainty estimates available: Yes, some

 

NACLIM (North Atlantic Climate)

NACLIM is a project funded by the European Union and is the follow up of the THOR (ThermoHaline Overturning – at Risk?) project. It involves the maintenance of a collection of transport time series of the North Atlantic Overflows and Atlantic inflow into the Nordic Seas. In particular the Faroe Bank Channel overflow, Hornbanki section Atlantic inflow volume and heat fluxes, Labrador Sea western boundary current transport at 53° N, Wyville Thomson Ridge overflow transport, Faroe Shetland Channel volume fluxes of Atlantic Water, Denmark Strait overflow transport, Iceland-Faroes Atlantic inflow, Kogur Array freshwater flux. The NACLIM project includes Hamburg University (Germany), Max Planck Institute (Germany), University Pierre et Marie Curie (France), Bergen University (Norway), Uni Research (Norway), GEOMAR (Germany), Denmark Meteorological Institute (Denmark), Havstovan (Faroe Islands), Finnish Meteorological Institute (Finland), Marine Research Institute (Iceland), Royal Netherlands Institute for Sea Research NIOZ (the Netherlands), The Scottish Association for Marine Science (UK), Natural Environment Research Council (UK), Nansen Center (Norway), Flemish Institution for Technological Research VITO (Belgium), Geographic Information Management (Belgium), Denmark Technical University (Denmark).

Record: Fluxes: 1992 to present; Hydrography: 1950 to present
Sampling: Hourly, daily, monthly, snapshots
Uncertainty estimates available: Yes, but not for all datasets. For details contact PIs or NACLIM Data Manager

 

Volume transport in Fram Strait

Data include volume transport derived from moored current meters and hydrographic sections. Maintained by the Alfred-Wegener Institution for Polar Research (Germany). 

Record: Aug-01-1997 to present; latest recovered and available data are from summer 2015
Sampling: Temperature and velocity are hourly; Derived volume transports are monthly
Uncertainty estimates available: No

 

Freshwater flux in Fram Strait

Data include liquid freshwater transport relative to a reference salinity of 34.9 in the East Greenland Current derived from six moorings in Fram Strait at 78°50'N. The freshwater transport does not include sea ice. The array has been maintained since 1997 up to present by the Norwegian Polar Institute (Norway). The freshwater transport product will soon become available as downloadable data. The update of freshwater transport up to September 2014 is expected late 2016.

Record: Sept-01-1997 to Aug-30-2009
Sampling: Raw salinity and velocity data vary from 5 minutes to 2 hours; Freshwater transport products are give as monthly means  
Uncertainty estimates available: Yes