Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Journal topic
Discussion papers
https://doi.org/10.5194/bg-2019-130
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-2019-130
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 16 Apr 2019

Research article | 16 Apr 2019

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Biogeosciences (BG).

Identifying areas prone to coastal hypoxia – the role of topography

Elina A. Virtanen1,2, Alf Norkko3,4, Antonia Nyström Sandman5, and Markku Viitasalo1 Elina A. Virtanen et al.
  • 1Marine Research Centre, Finnish Environment Institute, Helsinki, 00790, Finland
  • 2Department of Geosciences and Geography, University of Helsinki, Helsinki, 00014, Finland
  • 3Tvärminne Zoological Station, University of Helsinki, Hanko, 10900, Finland
  • 4Baltic Sea Centre, Stockholm University, Stockholm, 10691, Sweden
  • 5AquaBiota Water Research, Stockholm, 11550, Sweden

Abstract. Hypoxia is an increasing problem in marine ecosystems around the world, and recent projections indicate that anoxic dead zones will be spreading in the forthcoming decades. While major advances have been made in our understanding of the drivers of hypoxia, it fundamentally hinges on patterns of water circulation that can be difficult to resolve in coastal regions. The complexity of many coastal areas and lack of detailed in situ data has hindered the development of models describing oxygen dynamics at a sufficient resolution for efficient management actions to take place. We hypothesized that the enclosed nature of seafloors facilitates hypoxia formation. We developed simple proxies of seafloor heterogeneity and modelled oxygen deficiency in complex coastal areas in the northern Baltic Sea. We discovered that topographically sheltered seafloors and sinkholes with stagnant water are prone to the development of hypoxia. Approximately half of the monitoring sites in Stockholm Archipelago and one third of sites in southern Finland experienced severe hypoxia (O2 < 2 mg L−1). Based only on topography, area potentially affected by hypoxia is smaller than anticipated. Developed models could boost the performance of numerical models, aid nutrient abatement measures, and pinpoint areas where management actions are most urgently needed.

Elina A. Virtanen et al.
Interactive discussion
Status: open (extended)
Status: open (extended)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Elina A. Virtanen et al.
Elina A. Virtanen et al.
Viewed  
Total article views: 280 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
202 75 3 280 14 0 1
  • HTML: 202
  • PDF: 75
  • XML: 3
  • Total: 280
  • Supplement: 14
  • BibTeX: 0
  • EndNote: 1
Views and downloads (calculated since 16 Apr 2019)
Cumulative views and downloads (calculated since 16 Apr 2019)
Viewed (geographical distribution)  
Total article views: 240 (including HTML, PDF, and XML) Thereof 239 with geography defined and 1 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 15 Jun 2019
Publications Copernicus
Download
Short summary
We identified prone areas to oxygen loss in a complex marine area with a high probability without knowledge on biogeochemical properties. Sheltered, topographically heterogeneous areas, where water exchange is limited are more susceptible for developing hypoxia. Developed models could boost the performance of numerical models, aid nutrient abatement measures, explain why in some areas abatement actions do not work, and pinpoint areas where management actions are most urgently needed.
We identified prone areas to oxygen loss in a complex marine area with a high probability...
Citation