Preformed Properties for Marine Organic Matter and Carbonate Mineral Cycling Quantification. Issue 1 (29th December 2020)

• Record Type: Journal Article
• Authors: Carter, B. R.; Feely, R. A.; Lauvset, S. K.; Olsen, A.; DeVries, T.; Sonnerup, R.
• Is Part Of: Global biogeochemical cycles. Volume 35:Issue 1(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-29
• Subjects: Preformed Properties -- Carbonate Dissolution -- Oxygenation -- Carbon Cycling -- Circulation -- Biogeochemistry; Biogeochemical cycles -- Periodicals; Electronic journals; 577.1405
• DOI: 10.1029/2020GB006623
• Languages: English
• ISSNs: 0886-6236

Abstract

Abstract: We estimate preformed ocean phosphate, nitrate, oxygen, silicate, and alkalinity by combining a reconstruction of ventilation pathways in the ocean interior with estimates of submixed layer properties. These new preformed property estimates are intended to aid biogeochemical cycling studies and validation of modeled preformed property distributions and are available online. Analyses of net property accumulations (observed minus preformed properties) indicate net remineralization ratios in the ocean interior of [1 P]: [14.1 ± 0.6 N]: [−141 ± 12 O2 ]: [95 ± 25 Si]: [89 ± 9 TA]. These ratios imply that the interior ocean stores 1, 300 (±230) PgC through organic matter remineralization and 540 (±60) PgC through carbonate mineral dissolution and that apparent oxygen utilization can overestimate the interior ocean oxygen consumption by ~25%. Further, only 4 (±1%) and 46 (±5%) of the total alkalinity accumulated from carbonate mineral dissolution are found in seawater that is supersaturated with respect to the aragonite and calcite mineral forms of calcium carbonate, respectively. These small excess alkalinity inventories are due to smaller volumes of the supersaturated water masses and shorter ventilation timescales, as carbonate mineral dissolution rates appear nearly independent of depth and saturation state. Key Points: We have updated global preformed biogeochemical property estimates and provided the estimates for analysis and model validation The updated estimates support recent literature findings regarding remineralization ratios and deficiencies in apparent oxygen utilization Carbonate mineral dissolution rates are likely more uniform between saturation regimes than previously found