Spreading of overflow water from the Greenland to the Labrador Sea

In 1996, about 320 kg of SF6 were introduced in the center of the Greenland Sea gyre. We use this signal together with the CFC distribution to follow the spreading of Greenland gyre water from the Denmark Strait through the Irminger Basin and the Labrador Sea to the Grand Banks. In the summer of 2003 Denmark Strait Overflow Water tagged with deliberately released SF6 could be traced throughout the Irminger Basin to the central Labrador Sea, confirming that water with potential density of 28.045 contributes to the Denmark Strait Overflow. The upper limit of the transfer time from the central Greenland Sea to the Labrador Sea was found to be 7 years. This study suggests that roughly 4 kg of excess SF6 has been transported over the Denmark Strait and confirm earlier reported transport through the Faroe Bank Channel. These results should be considered when using SF6 as a transient tracer

Physical oceanography, CFC-11 and CFC-12 measured on water bottle samples during Maria S. Merian cruise MSM38

Temperature, salinity and the anthropogenic tracers measured on the RV Maria S. Merian Cruise MSM38 Cadiz - St. John's 05/07 - 06/05/2014 Chief Scientist: Dagmar Kieke Region: Subpolar North Atlanti

Noble gas (He, Ne isotopes) and transient tracer (CFC-11 and CFC-12) measurements from POLARSTERN cruise PS100 (northeast Greenland, 2016)

Noble gases (3He, 4He, 20Ne, 22Ne) In total we took 650 water samples for stable noble gas isotopes (3He, 4He, 20Ne, 22Ne) in copper tubes from 69 stations in Fram Strait, on the north-eastern Greenland shelf and nearby 79 North Glacier (79NG, Nioghalvfjerdsbræ). The water samples were stored from the CTD/water bottle system without contact to atmospheric air and preventing air bubbles into gas tight copper tubes, which are clamped of at both sides. In the IUP Bremen noble gas lab the samples were pre-processed with a UHV (ultra high vacuum) gas extraction system. Sample gases are transferred via water vapour into a glass ampoule kept at liquid nitrogen temperature. For analysis of the noble gas isotopes the glass ampoules are connected to a fully automated UHV mass spectrometric system equipped with a two stage cryogenic system. Regularly, the system is calibrated with atmospheric air standards (reproducibility <0.2%). Also measurement of line blanks and linearity are done. The performance of the Bremen facility is described in Sültenfuß et al. (2009). The total errors for the noble gas measurements are estimated to be 0.4% for 4He, 0.4% for total Ne, and 0.4% for δ3He. Chlorofluorocarbons (CFC-11, CFC-12) For the transient tracers (chlorofluorocarbons, CFC-11 and CFC-12), we took samples on 80 stations in Fram Strait, on the north-eastern Greenland shelf and nearby 79 North Glacier (79NG, Nioghalvfjerdsbræ). The Chlorofluorocarbon (CFC-11 and CFC-12) water samples from the CTD-bottle-system were stored in glass ampoules without contact to the atmosphere during the tapping. Immediately after sampling the ampoules are flame sealed after a CFC free headspace of pure nitrogen had been applied. The determination of CFC concentrations in the IUP Bremen gas chromatography lab is accomplished by purge and trap sample pre-treatment followed by gas chromatographic (GC) separation on a capillary column and electron capture detection (ECD). The system is calibrated by analyzing several different volumes of a known standard gas. The loss of CFCs into the headspace is considered by a careful equilibration between liquid and gas phase under controlled conditions before the sealed ampoules are opened and a precise measurement of the volume of the headspace. CFC concentrations are calibrated on SIO98 scale (Prinn et al., 2000). A more detailed description of the measurement system is given by Bulsiewicz et at. (1998). The overall accuracy is estimated to be 1.5% for CFC-11 and 1.0% for CFC-12. The accuracy accounts for uncertainties of calibrated sample volume, calibration curve, extraction efficiency, standard and working gas, water blank, etc. These noble-gas and CFC data are related to Kanzow et al. (2017). They will be first published in Huhn et al 2021, in prep). Acknowledgment We thank master and crew of FS Polarstern cruise PS 100. This work was partly funded by the DFG in the framework of the Priority Program SPP 1889 "Regional Sea Level and Society", grants RH25/43 to M. Rhein and HU 1544/7 to O. Huhn)

Physical oceanography and anthropogenic tracers measured on water bottle samples during Maria S. Merian cruise MSM28

Temperature, salinity and the anthropogenic tracers measured on the RV Maria S. Merian Cruise MSM28 St. John's - Tromsö 05/09 - 06/20/2013 Chief Scientist: Dagmar Kieke Region: Subpolar North Atlanti

Physical oceanography, CFC-11 and CFC-12 measured on water bottle samples during Maria S. Merian cruise MSM21/2

Temperature, salinity and CFCs measured on the RV Maria S. Merian Cruise MSM21/2 Reykjavik - Nuuk 25th June - 24th July 2012 Chief Scientist: Dagmar Kieke Region: Subpolar North Atlanti

Physical oceanography and anthropogenic tracers measured on water bottle samples during Maria S. Merian cruise MSM53

Temperature, salinity, oxygen data and anthropogenic tracers measured on the Maria S. Merian cruise MSM53 Kiel - St. John's 03/31 - 05/09/2016. Chief Scientist: Dagmar Kieke Region: Subpolar North Atlanti

Physical oceanography and anthropogenic tracers measured on water bottle samples during Maria S. Merian cruise MSM42

Temperature, salinity and anthropogenic tracers measured on the RV Maria S. Merian Cruise MSM42 Bermuda - St. John's 05/02 - 05/22/2015 Chief Scientist: Dagmar Kieke Region: around Flemish Cap, Orphan Basi

Physical oceanography, CFC-11 and CFC-12 measured on water bottle samples during cruise SUBPOLAR with RV Thalassa

Temperature, salinity, oxygen data and anthropogenic tracers measured on the RV Thalassa Cruise Subpolar Brest - St. John's 06/04 - 07/12/2005 Chief Scientist: Monika Rhein Region: Subpolar North Atlanti

Physical oceanography and anthropogenic tracers measured on water bottle samples during Maria S. Merian cruise MSM64

The bottle data on cruise MSM64 contain measurements of pressure, temperature, salinity and oxygen (derived from CTD values at the location of closing bottles) and direct measurements of oxygen, CFC-12 and SF6. The data were collected with the research vessel Maria S. Merian. Region: subpolar Northa Atlantic, 11°W-47°W, 47°N-54°N, Ports: Southampton - St. John's, Date: May 27 - June 23, 2017. The bottle data were collected by an SBE 32 water sampler system in connection with a SBE 911 plus CTD. CTD was mounted to a metal frame with 22 Niskin bottles of 10 l volume, which was lowered from the sea surface down to 10 m above the seafloor. Pressure, temperature, salinity and oxygen data from the CTD were recorded at the time when closing the bottles. In addition, direct samples of salinity and oxygen from the water bottles have been taken to calibrate the CTD data. The accuracy of the CTD measurements is: 1 dbar for pressure, 0.001 °C for temperature, 0.002 for salinity, 3.5 µmol/kg for oxygen. The oxygen samples from the Niskin bottles have been analysed by Winkler titration with an accuracy of 3.0 µmol/kg. In addition, samples for the analyses of CFC-12 and SF6 in the home lab have been stored in flame sealed glass ampoules of two sizes: ~100 ml and 220 ml. The samples have been analysed in the tracer lab at the University of Bremen (department of oceanography) by a capillary-chromatographic system with electron capture detector. This device is an advancement from the one described in: Bulsiewicz, K., H. Rose, O. Klatt, A. Putzka, and W. Roether (1998), A capillary -column chromatographic system for efficient chlorofluorocarbon measurement in ocean waters, J. Geophys, Res., 103, 15959-15970. CFC-12 and SF6 values are reported on the SIO-98 scale. Accuracy is 4% for SF6 and 2% for CFC-12, detection limt 0.02 fmol/kg for SF6 and 0.004 pmol/kg for CFC-12 (values are slightly better for the samples from the large ampoules)

Physical oceanography, CFC-11 and CFC-12 measured on water bottle samples during Maria S. Merian cruise MSM27

Temperature, salinity, oxygen data and anthropogenic tracers measured on the Maria S. Merian Cruise MSM27 St. John's - St. John's 04/19 - 05/06/2013 Chief Scientist: Dagmar Kieke Region: Flemish Pass, Orphan Basin, DWBC east of Flemish Ca