Magnitude, Trends, and Variability of the Global Ocean Carbon Sink From 1985 to 2018

DeVries, Tim; Yamamoto, Kana; Wanninkhof, Rik; Gruber, Nicolas; Hauck, Judith; Müller, Jens Daniel; Bopp, Laurent; Carroll, Dustin; Carter, Brendan; Chau, Thi‐Tuyet‐Trang; Doney, Scott C.; Gehlen, Marion; Gloege, Lucas; Gregor, Luke; Henson, Stephanie; Kim, Ji Hyun; Iida, Yosuke; Ilyina, Tatiana; Landschützer, Peter; Le Quéré, Corinne; ... (2023). Magnitude, Trends, and Variability of the Global Ocean Carbon Sink From 1985 to 2018. Global biogeochemical cycles, 37(10) American Geophysical Union 10.1029/2023GB007780

[img]
Preview
Text
Global_Biogeochemical_Cycles_-_2023_-_DeVries_-_Magnitude_Trends_and_Variability_of_the_Global_Ocean_Carbon_Sink_From-1.pdf - Published Version
Available under License Creative Commons: Attribution-Noncommercial (CC-BY-NC).

Download (4MB) | Preview

This contribution to the RECCAP2 (REgional Carbon Cycle Assessment and Processes) assessment analyzes the processes that determine the global ocean carbon sink, and its trends and variability over the period 1985–2018, using a combination of models and observation-based products. The mean sea-air CO2 flux from 1985 to 2018 is −1.6 ± 0.2 PgC yr−1 based on an ensemble of reconstructions of the history of sea surface pCO2 (pCO2 products). Models indicate that the dominant component of this flux is the net oceanic uptake of anthropogenic CO2, which is estimated at −2.1 ± 0.3 PgC yr−1 by an ensemble of ocean biogeochemical models, and −2.4 ± 0.1 PgC yr−1 by two ocean circulation inverse models. The ocean also degasses about 0.65 ± 0.3 PgC yr−1 of terrestrially derived CO2, but this process is not fully resolved by any of the models used here. From 2001 to 2018, the pCO2 products reconstruct a trend in the ocean carbon sink of −0.61 ± 0.12 PgC yr−1 decade−1, while biogeochemical models and inverse models diagnose an anthropogenic CO2-driven trend of −0.34 ± 0.06 and −0.41 ± 0.03 PgC yr−1 decade−1, respectively. This implies a climate-forced acceleration of the ocean carbon sink in recent decades, but there are still large uncertainties on the magnitude and cause of this trend. The interannual to decadal variability of the global carbon sink is mainly driven by climate variability, with the climate-driven variability exceeding the CO2-forced variability by 2–3 times. These results suggest that anthropogenic CO2 dominates the ocean CO2 sink, while climate-driven variability is potentially large but highly uncertain and not consistently captured across different methods.

Item Type:

Journal Article (Original Article)

Division/Institute:

08 Faculty of Science > Physics Institute > Climate and Environmental Physics
10 Strategic Research Centers > Oeschger Centre for Climate Change Research (OCCR)
08 Faculty of Science > Physics Institute

UniBE Contributor:

Terhaar, Jens

Subjects:

500 Science > 530 Physics
500 Science > 550 Earth sciences & geology

ISSN:

0886-6236

Publisher:

American Geophysical Union

Language:

English

Submitter:

Jens Terhaar

Date Deposited:

08 Mar 2024 14:39

Last Modified:

08 Mar 2024 14:39

Publisher DOI:

10.1029/2023GB007780

BORIS DOI:

10.48350/193965

URI:

https://boris.unibe.ch/id/eprint/193965

Actions (login required)

Edit item Edit item
Provide Feedback