Preprints
https://doi.org/10.5194/bg-2019-16
https://doi.org/10.5194/bg-2019-16
23 Jan 2019
 | 23 Jan 2019
Status: this preprint was under review for the journal BG but the revision was not accepted.

Drivers of 21st Century carbon cycle variability in the North Atlantic Ocean

Matthew P. Couldrey, Kevin I. C. Oliver, Andrew Yool, Paul R. Halloran, and Eric P. Achterberg

Abstract. The North Atlantic carbon sink is a prominent component of global climate, storing large amounts of atmospheric carbon dioxide (CO2), but this basin’s CO2 uptake variability presents challenges for future climate prediction. A comprehensive mechanistic understanding of the processes that give rise to year-to-year (interannual) and decade-to-decade (decadal) variability in the North Atlantic’s dissolved inorganic carbon (DIC) inventory is lacking. Here, we numerically simulate the oceanic response to human-induced (anthropogenic) climate change from the industrial era to the year 2100. The model distinguishes how different physical, chemical, and biological processes modify the basin’s DIC inventory; the saturation, soft tissue, and carbonate pumps, anthropogenic emissions, and other processes causing air-sea disequilibria. There are four ‘natural’ pools (saturation, soft tissue, carbonate, and disequilibrium), and an ‘anthropogenic’ pool. Interannual variability of the North Atlantic DIC inventory arises primarily due to temperature- and alkalinity-induced changes in carbon solubility (saturation concentrations). A mixture of saturation and anthropogenic drivers cause decadal variability. Multidecadal variability results from the opposing effects of saturation versus soft tissue carbon, and anthropogenic carbon uptake. By the year 2100, the North Atlantic gains 66 Pg (1 Pg = 1015 grams) of anthropogenic carbon, and the natural carbon pools collectively decline by 4.8 Pg. The first order controls on interannual variability of the North Atlantic carbon sink size are therefore largely physical, and the biological pump emerges as an important driver of change on multidecadal timescales. Further work should identify specifically which physical processes underlie the interannual saturation-dominated DIC variability documented here.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Matthew P. Couldrey, Kevin I. C. Oliver, Andrew Yool, Paul R. Halloran, and Eric P. Achterberg
 
Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
 
Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
Matthew P. Couldrey, Kevin I. C. Oliver, Andrew Yool, Paul R. Halloran, and Eric P. Achterberg
Matthew P. Couldrey, Kevin I. C. Oliver, Andrew Yool, Paul R. Halloran, and Eric P. Achterberg

Viewed

Total article views: 1,229 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
809 369 51 1,229 42 43
  • HTML: 809
  • PDF: 369
  • XML: 51
  • Total: 1,229
  • BibTeX: 42
  • EndNote: 43
Views and downloads (calculated since 23 Jan 2019)
Cumulative views and downloads (calculated since 23 Jan 2019)

Viewed (geographical distribution)

Total article views: 1,021 (including HTML, PDF, and XML) Thereof 1,020 with geography defined and 1 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Latest update: 25 May 2024
Download
Short summary
Determining how much carbon dioxide (CO2) the oceans absorb is key to predicting human-caused climate change. A computer model of the ocean shows how the North Atlantic will change up to the end of the century. Year-to-year variations are mostly caused by changes in ocean temperature and seawater chemistry, altering CO2 solubility. By 2100, human emissions cause the biggest changes. The near term changes are physically driven, which may be more predictable than biological changes.
Altmetrics