IMAS Metadata Catalogue
An improved model of particle attenuation reduces estimates of Southern Ocean carbon transfer efficiency
The downward transport of organic particles produced by marine organisms is a key control on the ocean's carbon storage. Measurements of particle attenuation through the water column have historically been used to infer the sequestration potential of the biological carbon pump. While often modelled using a single power-law fit, this simplification may obscure important depth-dependent processes.
Using data from biogeochemical-Argo floats in the Southern Ocean, here we show that splitting the water column into two distinct regimes captures depth-dependent variability in particle attenuation more effectively. Compared to the single power-law fit the model reveals greater attenuation just below the productive layer, reducing particulate organic carbon flux into the mesopelagic (200 - 400 m) by 40 - 60 %.
Our findings suggest a more mechanistic representation of particle attenuation is needed to improve estimates of carbon transport and the durability of biologically-based marine carbon dioxide removal technologies, and to reduce uncertainties in ocean-climate feedbacks and future climate projections.
Simple
Identification info
- Date (Publication)
- 2025-11-24T00:00:00
Identifier
- Title
- Information and documentation - Digital object identifier system
- Citation identifier
- ISO 26324:2012
- Code
- 10.25959/4t8m-a057
- Codespace
- doi.org
- Description
- Digital Object Identifier (DOI)
Resource provider
Principal investigator
- Credit
- The Argo Program is part of the Global Ocean Observing System and part of the Argo data were collected and made freely available by the Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) Project funded by the National Science Foundation, Division of Polar Programs (NSF PLR -1425989, extension NSF OPP-1936222), supplemented by NASA, and by the International Argo Program and the NOAA programs that contribute to it. (http://www.argo.ucsd.edu, http://argo.jcommops.org). The Ssalto/Duacs altimeter products were produced and distributed by the Copernicus Marine and Environment Monitoring Service (CMEMS) (http://www.marine.copernicus.eu). PAR and backscatter data were obtained from the Moderate Resolution Imaging Spectroradiometer aboard the NASA satellite (Aqua-MODIS). We use the seasonal climatology (21 December through 20 March of the following year, 2002-2023), 9 km spatial resolution. This research was supported by the Australian Research Council Special Research Initiative, Australian Centre for Excellence in Antarctic Science (ACEAS) (Project Number SR200100008) and Antarctic Gateway Partnership (Project ID SR140300001).
- Status
- On going
Point of contact
- Topic category
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- Oceans
Extent
))
Temporal extent
- Time period
- 2023-09-01
- Maintenance and update frequency
- As needed
- Keywords (Theme)
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- BGC Argo floats
- carbon pump
- Southern Ocean
- phytoplankton
- Global Change Master Directory Earth Science Keywords, Version 8.5
Resource constraints
- Linkage
-
https://licensebuttons.net/l/by/4.0/88x31.png
License Graphic
- Title
- Creative Commons Attribution 4.0 International License
- Alternate title
- CC-BY
- Edition
- 4.0
- Website
-
https://creativecommons.org/licenses/by/4.0/
License Text
- Other constraints
- Cite data as: Oetjens, A., Rohr, T., Strutton, P., & Chase, Z. (2025). An improved model of particle attenuation reduces estimates of Southern Ocean carbon transfer efficiency [Data set]. Institute for Marine and Antarctic Studies. https://doi.org/10.25959/4T8M-A057
- Language
- English
- Character encoding
- UTF8
Content Information
- Content type
- Physical measurement
Distribution Information
- Distribution format
-
- NetCDF, .png, .jpg, .py
Resource lineage
- Statement
- BGC-Argo data were collected and made freely available by the International Argo Program and the national programs that contribute to it. Initial QC and corrections of the float data used in this analysis were performed at three data assembly centers (DACs): NOAA AOML in the USA, IFREMER in France and CSIRO in Australia. We use only corrected data (adjusted or delayed-mode) in the analysis. Float observations were filtered for good data with reference to Argo quality control flags (1, 2, 5, 8). Temperature and salinity profiles were linearly interpolated onto a 1 dbar pressure grid. Chlorophyll fluorescence profiles were smoothed by a 7 point running mean in the vertical before interpolation at 1 dbar. We followed schallenberg et al. (2020) and applied the Southern Ocean specific correction factor of 3.79 to the data (after removing the already applied global correction factor of 2). For backscatter, we cut off values above 0.04 1/m since this is the saturation limit of the detector (Bif et al. 2024). Next, we applied a rolling minimum followed by a rolling maximum to remove spikes \citep{briggs_method_2013} before interpolated to 1 dbar. This preprocessing is done before applying the Koestner et al. (2024) algorithm to convert to POC. Following Arteaga et al. (2022) we use the BGC-Argo modified version of the Carbon based Productivity Model (CbPM) first introduced by Westberry et al. (2008) and Behrenfeld et al. (2005) to compute net primary production (NPP).
- Hierarchy level
- Dataset
- Hierarchy level
- Dataset
Metadata
- Metadata identifier
- urn:uuid/840b2f5c-1509-4afb-8f14-9af8582ef09d
- Language
- English
- Character encoding
- UTF8
Type of resource
- Resource scope
- Dataset
- Name
- IMAS Dataset level record
- Metadata linkage
-
https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/840b2f5c-1509-4afb-8f14-9af8582ef09d
Point of truth URL of this metadata record
- Date info (Creation)
- 2025-11-24T00:00:00
- Date info (Revision)
- 2025-12-03T17:26:09
Metadata standard
- Title
- ISO 19115-3:2018
Overviews
Spatial extent
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