The Southern Ocean Carbon Cycle 1985–2018: Mean, Seasonal Cycle, Trends, and Storage ...

• Main Authors: Hauck, Judith, Gregor, Luke, Nissen, Cara, Patara, Lavinia, Hague, Mark, Mongwe, Precious, Bushinsky, Seth, Doney, Scott C., Gruber, Nicolas, Le Quéré, Corinne, Manizza, Manfredi, Mazloff, Matthew, Monteiro, Pedro M.S., Terhaar, Jens
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2023
• Subjects: Southern Ocean
• Online Access: https://dx.doi.org/10.3929/ethz-b-000642558; http://hdl.handle.net/20.500.11850/642558

We assess the Southern Ocean CO₂ uptake (1985–2018) using data sets gathered in the REgional Carbon Cycle Assessment and Processes Project Phase 2. The Southern Ocean acted as a sink for CO₂ with close agreement between simulation results from global ocean biogeochemistry models (GOBMs, 0.75 ± 0.28 PgC yr⁻¹) and pCO₂-observation-based products (0.73 ± 0.07 PgC yr⁻¹). This sink is only half that reported by RECCAP1 for the same region and timeframe. The present-day net uptake is to first order a response to rising atmospheric CO₂, driving large amounts of anthropogenic CO₂ (Cant) into the ocean, thereby overcompensating the loss of natural CO2 to the atmosphere. An apparent knowledge gap is the increase of the sink since 2000, with pCO₂-products suggesting a growth that is more than twice as strong and uncertain as that of GOBMs (0.26 ± 0.06 and 0.11 ± 0.03 Pg C yr⁻¹ decade⁻¹, respectively). This is despite nearly identical pCO₂ trends in GOBMs and pCO2-products when both products are compared only at the ... : Global Biogeochemical Cycles, 37 (11) ...