Physical oceanography and CFC measured on water bottle samples during METEOR cruise M53/3
Repeated observations of CFC-11 and CFC-12 in the western tropical Atlantic over the period from 1990 to 2002 are used to fit parameters of the age spectra for several North Atlantic Deep Water components: the upper Labrador Sea water (ULSW), the Labrador Sea water (LSW), and the lower North Atlanti...
Main Authors: | , |
---|---|
Format: | Dataset |
Language: | English |
Published: |
PANGAEA
2017
|
Subjects: | |
Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.872010 https://doi.org/10.1594/PANGAEA.872010 |
id |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.872010 |
---|---|
record_format |
openpolar |
spelling |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.872010 2023-05-15T16:00:42+02:00 Physical oceanography and CFC measured on water bottle samples during METEOR cruise M53/3 Steinfeldt, Reiner Rhein, Monika MEDIAN LATITUDE: 11.327486 * MEDIAN LONGITUDE: -53.888418 * SOUTH-BOUND LATITUDE: -4.363830 * WEST-BOUND LONGITUDE: -61.558000 * NORTH-BOUND LATITUDE: 16.312833 * EAST-BOUND LONGITUDE: -34.288833 * DATE/TIME START: 2002-06-08T13:35:00 * DATE/TIME END: 2002-07-02T20:15:00 * MINIMUM DEPTH, water: 2.78 m * MAXIMUM DEPTH, water: 5602.70 m 2017-02-13 text/tab-separated-values, 10153 data points https://doi.pangaea.de/10.1594/PANGAEA.872010 https://doi.org/10.1594/PANGAEA.872010 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.872010 https://doi.org/10.1594/PANGAEA.872010 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Steinfeldt, Reiner; Rhein, Monika (2004): Spreading velocities and dilution of North Atlantic Deep Water in the tropical Atlantic based on CFC time series. Journal of Geophysical Research: Oceans, 109(C3), C03046, https://doi.org/10.1029/2003JC002050 1 10 100 101 102 103 104 11 12 13 14 15 16 17 18 19 2 20 21 22 23 24 25 3 30 31 32 33 34 35 37 38 39 4 40 41 42 43 44 45 46 47 48 5 50 51 52 53 54 55 Dataset 2017 ftpangaea https://doi.org/10.1594/PANGAEA.872010 https://doi.org/10.1029/2003JC002050 2023-01-20T09:08:35Z Repeated observations of CFC-11 and CFC-12 in the western tropical Atlantic over the period from 1990 to 2002 are used to fit parameters of the age spectra for several North Atlantic Deep Water components: the upper Labrador Sea water (ULSW), the Labrador Sea water (LSW), and the lower North Atlantic Deep Water (LNADW). The most robust results are the mean spreading velocities, u, from the formation region in the Labrador Sea and the Denmark Strait, of 1.5 ± 0.3 cm/s for the two LSW water masses and 2.0 ± 0.2 cm/s for LNADW, respectively. These values are equivalent to an age of about 15–22 years for all three components at 16°N and 21–31 years at the equator at 35°W. The results are compatible with simpler tracer methods, as CFC ratios or “effective” ages. The fractions, f, of the “young” component (i.e., the fraction of the water mass ventilated in the last 50 years), turned out to be quite small, ranging from 25% to less than 5%. The downstream decrease of f indicates mixing of young NADW with CFC-poor older NADW vintages and/or mixing with other CFC-free water masses from the Southern Hemisphere. The lowest fractions were found in the LNADW, with a sharp downstream decrease from the equator at 35°W to 10°S, probably caused by the bifurcation into a zonal flow along 2°S and a southward flow along the Brazilian coast. Unlike the small uncertainties estimated for the inferred velocities, isopycnal diffusivities, k, range from 100 to 10000 m**2/s. The temporal evolution of f in the LSW shows a maximum, propagating from 7°N in 1996, downstream to 5°S in the Deep Western Boundary Current, and along 2°S to 23°W. We interpret this signal as the arrival of the intensely ventilated LSW formed in 1972–1976. Decreasing fractions of the ULSW and LSW south of the equator between 2000 and 2002 are presumably caused by local dynamics. Dataset Denmark Strait Labrador Sea NADW North Atlantic Deep Water North Atlantic PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-61.558000,-34.288833,16.312833,-4.363830) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
1 10 100 101 102 103 104 11 12 13 14 15 16 17 18 19 2 20 21 22 23 24 25 3 30 31 32 33 34 35 37 38 39 4 40 41 42 43 44 45 46 47 48 5 50 51 52 53 54 55 |
spellingShingle |
1 10 100 101 102 103 104 11 12 13 14 15 16 17 18 19 2 20 21 22 23 24 25 3 30 31 32 33 34 35 37 38 39 4 40 41 42 43 44 45 46 47 48 5 50 51 52 53 54 55 Steinfeldt, Reiner Rhein, Monika Physical oceanography and CFC measured on water bottle samples during METEOR cruise M53/3 |
topic_facet |
1 10 100 101 102 103 104 11 12 13 14 15 16 17 18 19 2 20 21 22 23 24 25 3 30 31 32 33 34 35 37 38 39 4 40 41 42 43 44 45 46 47 48 5 50 51 52 53 54 55 |
description |
Repeated observations of CFC-11 and CFC-12 in the western tropical Atlantic over the period from 1990 to 2002 are used to fit parameters of the age spectra for several North Atlantic Deep Water components: the upper Labrador Sea water (ULSW), the Labrador Sea water (LSW), and the lower North Atlantic Deep Water (LNADW). The most robust results are the mean spreading velocities, u, from the formation region in the Labrador Sea and the Denmark Strait, of 1.5 ± 0.3 cm/s for the two LSW water masses and 2.0 ± 0.2 cm/s for LNADW, respectively. These values are equivalent to an age of about 15–22 years for all three components at 16°N and 21–31 years at the equator at 35°W. The results are compatible with simpler tracer methods, as CFC ratios or “effective” ages. The fractions, f, of the “young” component (i.e., the fraction of the water mass ventilated in the last 50 years), turned out to be quite small, ranging from 25% to less than 5%. The downstream decrease of f indicates mixing of young NADW with CFC-poor older NADW vintages and/or mixing with other CFC-free water masses from the Southern Hemisphere. The lowest fractions were found in the LNADW, with a sharp downstream decrease from the equator at 35°W to 10°S, probably caused by the bifurcation into a zonal flow along 2°S and a southward flow along the Brazilian coast. Unlike the small uncertainties estimated for the inferred velocities, isopycnal diffusivities, k, range from 100 to 10000 m**2/s. The temporal evolution of f in the LSW shows a maximum, propagating from 7°N in 1996, downstream to 5°S in the Deep Western Boundary Current, and along 2°S to 23°W. We interpret this signal as the arrival of the intensely ventilated LSW formed in 1972–1976. Decreasing fractions of the ULSW and LSW south of the equator between 2000 and 2002 are presumably caused by local dynamics. |
format |
Dataset |
author |
Steinfeldt, Reiner Rhein, Monika |
author_facet |
Steinfeldt, Reiner Rhein, Monika |
author_sort |
Steinfeldt, Reiner |
title |
Physical oceanography and CFC measured on water bottle samples during METEOR cruise M53/3 |
title_short |
Physical oceanography and CFC measured on water bottle samples during METEOR cruise M53/3 |
title_full |
Physical oceanography and CFC measured on water bottle samples during METEOR cruise M53/3 |
title_fullStr |
Physical oceanography and CFC measured on water bottle samples during METEOR cruise M53/3 |
title_full_unstemmed |
Physical oceanography and CFC measured on water bottle samples during METEOR cruise M53/3 |
title_sort |
physical oceanography and cfc measured on water bottle samples during meteor cruise m53/3 |
publisher |
PANGAEA |
publishDate |
2017 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.872010 https://doi.org/10.1594/PANGAEA.872010 |
op_coverage |
MEDIAN LATITUDE: 11.327486 * MEDIAN LONGITUDE: -53.888418 * SOUTH-BOUND LATITUDE: -4.363830 * WEST-BOUND LONGITUDE: -61.558000 * NORTH-BOUND LATITUDE: 16.312833 * EAST-BOUND LONGITUDE: -34.288833 * DATE/TIME START: 2002-06-08T13:35:00 * DATE/TIME END: 2002-07-02T20:15:00 * MINIMUM DEPTH, water: 2.78 m * MAXIMUM DEPTH, water: 5602.70 m |
long_lat |
ENVELOPE(-61.558000,-34.288833,16.312833,-4.363830) |
genre |
Denmark Strait Labrador Sea NADW North Atlantic Deep Water North Atlantic |
genre_facet |
Denmark Strait Labrador Sea NADW North Atlantic Deep Water North Atlantic |
op_source |
Supplement to: Steinfeldt, Reiner; Rhein, Monika (2004): Spreading velocities and dilution of North Atlantic Deep Water in the tropical Atlantic based on CFC time series. Journal of Geophysical Research: Oceans, 109(C3), C03046, https://doi.org/10.1029/2003JC002050 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.872010 https://doi.org/10.1594/PANGAEA.872010 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.872010 https://doi.org/10.1029/2003JC002050 |
_version_ |
1766396716978798592 |