Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2
The Southern Ocean is highly under-sampled for the purpose of assessing total carbon uptake and its variability. Since this region dominates the mean global ocean sink for anthropogenic carbon, understanding temporal change is critical. Underway measurements of p CO 2 collected as part of the Drake...
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ftcopernicus:oai:publications.copernicus.org:bg63406 2023-05-15T16:02:23+02:00 Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2 Fay, Amanda R. Lovenduski, Nicole S. McKinley, Galen A. Munro, David R. Sweeney, Colm Gray, Alison R. Landschützer, Peter Stephens, Britton B. Takahashi, Taro Williams, Nancy 2018-09-27 application/pdf https://doi.org/10.5194/bg-15-3841-2018 https://www.biogeosciences.net/15/3841/2018/ eng eng doi:10.5194/bg-15-3841-2018 https://www.biogeosciences.net/15/3841/2018/ eISSN: 1726-4189 Text 2018 ftcopernicus https://doi.org/10.5194/bg-15-3841-2018 2019-12-24T09:50:07Z The Southern Ocean is highly under-sampled for the purpose of assessing total carbon uptake and its variability. Since this region dominates the mean global ocean sink for anthropogenic carbon, understanding temporal change is critical. Underway measurements of p CO 2 collected as part of the Drake Passage Time-series (DPT) program that began in 2002 inform our understanding of seasonally changing air–sea gradients in p CO 2 , and by inference the carbon flux in this region. Here, we utilize available p CO 2 observations to evaluate how the seasonal cycle, interannual variability, and long-term trends in surface ocean p CO 2 in the Drake Passage region compare to that of the broader subpolar Southern Ocean. Our results indicate that the Drake Passage is representative of the broader region in both seasonality and long-term p CO 2 trends, as evident through the agreement of timing and amplitude of seasonal cycles as well as trend magnitudes both seasonally and annually. The high temporal density of sampling by the DPT is critical to constraining estimates of the seasonal cycle of surface p CO 2 in this region, as winter data remain sparse in areas outside of the Drake Passage. An increase in winter data would aid in reduction of uncertainty levels. On average over the period 2002–2016, data show that carbon uptake has strengthened with annual surface ocean p CO 2 trends in the Drake Passage and the broader subpolar Southern Ocean less than the global atmospheric trend. Analysis of spatial correlation shows Drake Passage p CO 2 to be representative of p CO 2 and its variability up to several hundred kilometers away from the region. We also compare DPT data from 2016 and 2017 to contemporaneous p CO 2 estimates from autonomous biogeochemical floats deployed as part of the Southern Ocean Carbon and Climate Observations and Modeling project (SOCCOM) so as to highlight the opportunity for evaluating data collected on autonomous observational platforms. Though SOCCOM floats sparsely sample the Drake Passage region for 2016–2017 compared to the Drake Passage Time-series, their p CO 2 estimates fall within the range of underway observations given the uncertainty on the estimates. Going forward, continuation of the Drake Passage Time-series will reduce uncertainties in Southern Ocean carbon uptake seasonality, variability, and trends, and provide an invaluable independent dataset for post-deployment assessment of sensors on autonomous floats. Together, these datasets will vastly increase our ability to monitor change in the ocean carbon sink. Text Drake Passage Southern Ocean Copernicus Publications: E-Journals Drake Passage Southern Ocean Biogeosciences 15 12 3841 3855 |
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Copernicus Publications: E-Journals |
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ftcopernicus |
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English |
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The Southern Ocean is highly under-sampled for the purpose of assessing total carbon uptake and its variability. Since this region dominates the mean global ocean sink for anthropogenic carbon, understanding temporal change is critical. Underway measurements of p CO 2 collected as part of the Drake Passage Time-series (DPT) program that began in 2002 inform our understanding of seasonally changing air–sea gradients in p CO 2 , and by inference the carbon flux in this region. Here, we utilize available p CO 2 observations to evaluate how the seasonal cycle, interannual variability, and long-term trends in surface ocean p CO 2 in the Drake Passage region compare to that of the broader subpolar Southern Ocean. Our results indicate that the Drake Passage is representative of the broader region in both seasonality and long-term p CO 2 trends, as evident through the agreement of timing and amplitude of seasonal cycles as well as trend magnitudes both seasonally and annually. The high temporal density of sampling by the DPT is critical to constraining estimates of the seasonal cycle of surface p CO 2 in this region, as winter data remain sparse in areas outside of the Drake Passage. An increase in winter data would aid in reduction of uncertainty levels. On average over the period 2002–2016, data show that carbon uptake has strengthened with annual surface ocean p CO 2 trends in the Drake Passage and the broader subpolar Southern Ocean less than the global atmospheric trend. Analysis of spatial correlation shows Drake Passage p CO 2 to be representative of p CO 2 and its variability up to several hundred kilometers away from the region. We also compare DPT data from 2016 and 2017 to contemporaneous p CO 2 estimates from autonomous biogeochemical floats deployed as part of the Southern Ocean Carbon and Climate Observations and Modeling project (SOCCOM) so as to highlight the opportunity for evaluating data collected on autonomous observational platforms. Though SOCCOM floats sparsely sample the Drake Passage region for 2016–2017 compared to the Drake Passage Time-series, their p CO 2 estimates fall within the range of underway observations given the uncertainty on the estimates. Going forward, continuation of the Drake Passage Time-series will reduce uncertainties in Southern Ocean carbon uptake seasonality, variability, and trends, and provide an invaluable independent dataset for post-deployment assessment of sensors on autonomous floats. Together, these datasets will vastly increase our ability to monitor change in the ocean carbon sink. |
format |
Text |
author |
Fay, Amanda R. Lovenduski, Nicole S. McKinley, Galen A. Munro, David R. Sweeney, Colm Gray, Alison R. Landschützer, Peter Stephens, Britton B. Takahashi, Taro Williams, Nancy |
spellingShingle |
Fay, Amanda R. Lovenduski, Nicole S. McKinley, Galen A. Munro, David R. Sweeney, Colm Gray, Alison R. Landschützer, Peter Stephens, Britton B. Takahashi, Taro Williams, Nancy Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2 |
author_facet |
Fay, Amanda R. Lovenduski, Nicole S. McKinley, Galen A. Munro, David R. Sweeney, Colm Gray, Alison R. Landschützer, Peter Stephens, Britton B. Takahashi, Taro Williams, Nancy |
author_sort |
Fay, Amanda R. |
title |
Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2 |
title_short |
Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2 |
title_full |
Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2 |
title_fullStr |
Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2 |
title_full_unstemmed |
Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2 |
title_sort |
utilizing the drake passage time-series to understand variability and change in subpolar southern ocean pco2 |
publishDate |
2018 |
url |
https://doi.org/10.5194/bg-15-3841-2018 https://www.biogeosciences.net/15/3841/2018/ |
geographic |
Drake Passage Southern Ocean |
geographic_facet |
Drake Passage Southern Ocean |
genre |
Drake Passage Southern Ocean |
genre_facet |
Drake Passage Southern Ocean |
op_source |
eISSN: 1726-4189 |
op_relation |
doi:10.5194/bg-15-3841-2018 https://www.biogeosciences.net/15/3841/2018/ |
op_doi |
https://doi.org/10.5194/bg-15-3841-2018 |
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Biogeosciences |
container_volume |
15 |
container_issue |
12 |
container_start_page |
3841 |
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3855 |
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