Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf?
This study provides dissolved and particulate 230Th and 232Th results as well as particulate 234Th data collected during expeditions to the central Arctic Ocean (GEOTRACES, an international project to identify processes and quantify fluxes that control the distributions of trace elements; sections G...
| Main Authors: | , , , , , , , , , , , , |
|---|---|
| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2020
|
| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/143623 |
| _version_ | 1826120691411320832 |
|---|---|
| author | Valk, Ole Rutgers van der Loeff, Michiel M. Geibert, Walter Gdaniec, Sandra Moran, S. Bradley Lepore, Kate Edwards, Robert Lawrence Lu, Yanbin Puigcorbé, Viena Casacuberta, Nuria Paffrath, Ronja Smethie, William Roy-Barman, Matthieu |
| author2 | Earth Observatory of Singapore |
| author_facet | Earth Observatory of Singapore Valk, Ole Rutgers van der Loeff, Michiel M. Geibert, Walter Gdaniec, Sandra Moran, S. Bradley Lepore, Kate Edwards, Robert Lawrence Lu, Yanbin Puigcorbé, Viena Casacuberta, Nuria Paffrath, Ronja Smethie, William Roy-Barman, Matthieu |
| author_sort | Valk, Ole |
| collection | NTU |
| description | This study provides dissolved and particulate 230Th and 232Th results as well as particulate 234Th data collected during expeditions to the central Arctic Ocean (GEOTRACES, an international project to identify processes and quantify fluxes that control the distributions of trace elements; sections GN04 and GIPY11). Constructing a time series of dissolved 230Th from 1991 to 2015 enables the identification of processes that control the temporal development of 230Th distributions in the Amundsen Basin. After 2007, 230Th concentrations decreased significantly over the entire water column, particularly between 300 and 1500 m. This decrease is accompanied by a circulation change, evidenced by a concomitant increase in salinity. A potentially increased inflow of water of Atlantic origin with low dissolved 230Th concentrations leads to the observed depletion in dissolved 230Th in the central Arctic. Because atmospherically derived tracers (chlorofluorocarbon (CFC), sulfur hexafluoride (SF6)) do not reveal an increase in ventilation rate, it is suggested that these interior waters have undergone enhanced scavenging of Th during transit from Fram Strait and the Barents Sea to the central Amundsen Basin. The 230Th depletion propagates downward in the water column by settling particles and reversible scavenging. |
| first_indexed | 2024-10-01T05:20:55Z |
| format | Journal Article |
| id | ntu-10356/143623 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T05:20:55Z |
| publishDate | 2020 |
| record_format | dspace |
| spelling | ntu-10356/1436232020-09-26T21:30:54Z Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf? Valk, Ole Rutgers van der Loeff, Michiel M. Geibert, Walter Gdaniec, Sandra Moran, S. Bradley Lepore, Kate Edwards, Robert Lawrence Lu, Yanbin Puigcorbé, Viena Casacuberta, Nuria Paffrath, Ronja Smethie, William Roy-Barman, Matthieu Earth Observatory of Singapore Engineering::Environmental engineering Amundsen Basin Increased Scavenging This study provides dissolved and particulate 230Th and 232Th results as well as particulate 234Th data collected during expeditions to the central Arctic Ocean (GEOTRACES, an international project to identify processes and quantify fluxes that control the distributions of trace elements; sections GN04 and GIPY11). Constructing a time series of dissolved 230Th from 1991 to 2015 enables the identification of processes that control the temporal development of 230Th distributions in the Amundsen Basin. After 2007, 230Th concentrations decreased significantly over the entire water column, particularly between 300 and 1500 m. This decrease is accompanied by a circulation change, evidenced by a concomitant increase in salinity. A potentially increased inflow of water of Atlantic origin with low dissolved 230Th concentrations leads to the observed depletion in dissolved 230Th in the central Arctic. Because atmospherically derived tracers (chlorofluorocarbon (CFC), sulfur hexafluoride (SF6)) do not reveal an increase in ventilation rate, it is suggested that these interior waters have undergone enhanced scavenging of Th during transit from Fram Strait and the Barents Sea to the central Amundsen Basin. The 230Th depletion propagates downward in the water column by settling particles and reversible scavenging. Published version 2020-09-14T08:54:59Z 2020-09-14T08:54:59Z 2020 Journal Article Valk, O., Rutgers van der Loeff, M. M., Geibert, W., Gdaniec, S., Moran, S. B., Lepore, K., . . . Roy-Barman, M. (2020). Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf? Ocean Science, 16(1), 221-234. doi:10.5194/os-16-221-2020 1812-0784 https://hdl.handle.net/10356/143623 10.5194/os-16-221-2020 1 16 221 234 en Ocean Science © 2020 The Author(s) (Published by Copernicus Publications on behalf of the European Geosciences Union). This work is distributed under the Creative Commons Attribution 4.0 License. application/pdf |
| spellingShingle | Engineering::Environmental engineering Amundsen Basin Increased Scavenging Valk, Ole Rutgers van der Loeff, Michiel M. Geibert, Walter Gdaniec, Sandra Moran, S. Bradley Lepore, Kate Edwards, Robert Lawrence Lu, Yanbin Puigcorbé, Viena Casacuberta, Nuria Paffrath, Ronja Smethie, William Roy-Barman, Matthieu Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf? |
| title | Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf? |
| title_full | Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf? |
| title_fullStr | Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf? |
| title_full_unstemmed | Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf? |
| title_short | Decrease in 230Th in the Amundsen Basin since 2007 : far-field effect of increased scavenging on the shelf? |
| title_sort | decrease in 230th in the amundsen basin since 2007 far field effect of increased scavenging on the shelf |
| topic | Engineering::Environmental engineering Amundsen Basin Increased Scavenging |
| url | https://hdl.handle.net/10356/143623 |
| work_keys_str_mv | AT valkole decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT rutgersvanderloeffmichielm decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT geibertwalter decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT gdaniecsandra decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT moransbradley decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT leporekate decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT edwardsrobertlawrence decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT luyanbin decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT puigcorbeviena decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT casacubertanuria decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT paffrathronja decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT smethiewilliam decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf AT roybarmanmatthieu decreasein230thintheamundsenbasinsince2007farfieldeffectofincreasedscavengingontheshelf |