State of the Baltic Sea

The Baltic Sea is one of the world's most polluted seas. The pressure with the most negative impact on the ecosystem is eutrophication [1] caused by a surplus of phosphorus and nitrogen. This leads to many harmful effects on water quality such as dead bottoms, algae blooms, fish mortality, and poor water transparency. Eutrophication throws out of sync the delicate balance that exists in any aquatic environment and creates a negative feedback loop.

A lot has been done to diminish the inflow of nutrients especially in areas such as sewage treatment and agriculture. But we still need to reduce these nutrients, particularly phosphorus, before we have reached a point where the Baltic Sea starts curing itself. That is why we focus our projects on reducing phosphorus (and we always select projects based on their cost efficiency and impact potential).

  • The Baltic Sea is one of the world's most polluted seas and has a dead zone larger than one and a half times the size of Denmark, equivalent to more than one fifth of the seafloor [2, 3]

  • More than 80 000 km² suffer from hypoxia or anoxia, making it arguably the largest environmental problem in the region [3]

  • Of the various environmental pressures on the Baltic Sea, eutrophication has by far the largest impact on the Baltic Sea ecosystem [4]

  • 97% of the Baltic Sea suffers from eutrophication [5]

  • Eutrophication is what causes dead zones and algae blooms, making the water toxic

  • Eutrophication is caused by an excess of the nutrients, nitrogen and phosphorus, entering the sea [6]

  • With the right actions, the financial value in solving it substantially outweighs the cost [7]

  • If we manage to get the nutrient inflow to below Maximum Allowable Input (“MAI”), the Baltic Sea will start restoring itself (see picture below) [8]

Waterborne and total nutrient inputs

Extent of hypoxic & anoxic bottom water

Source: © GLOBAÏA www.globaia.org

 

Eutrophication and the planetary boundaries

The flow of nitrogen and phosphorus, that causes eutrophication, is not only a local problem but one of the most pressing global problems.

The latest Planetary Boundaries update indicates that six out of nine boundaries have been crossed, suggesting that Earth is now well outside of the safe operating space for humanity [9]. Among these, biogeochemical flows (nitrogen and phosphorus) are among the most significantly exceeded. Since the 2015 update, the degree of transgression for previously transgressed boundaries - biogeochemical flows, climate change, biosphere integrity, and land system change - has increased.

Our organisation started with a global perspective on how we could make the most positive impact on the environment. After a few years working on global environmental problems, it became evident that focusing on our own region’s largest environmental problem is also the best way to improve the environment globally.

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Sources

[1] Cumulative impacts on the marine environment, HELCOM (2018E)

[2] Greenpeace International, “The Baltic Sea, A Roadmap to Recovery” and many more

[3] SMHI ” Oxygen Survey in the Baltic Sea 2023 - Extent of Anoxia and Hypoxia, 1960 – 2023
RO_76 Oxygen Survey in the Baltic Sea 2023 - Extent of Anoxia and Hypoxia, 1960-2023 .pdf (smhi.se)

[4] Baltic Sea Impact Index, Halpern et al. (2008), Projekt HARMONY (Andersen et al. 2013), and HOLAS II (HELCOM 2018)

[5] Helcom "State of the Baltic Sea"

[6] Baltic Sea Environment Proceedings No. 115 B

[7] Boston Consulting Group Report, “Turning adversity into opportunity”, 2013 derived the economic value add which widely outreach all cost estimations.

[8] MAI are targets for nutrient inputs agreed upon by the Baltic States. If the MAI’s are met, the Baltic Sea is assumed to restore itself. HELCOM Inputs of nutrients (nitrogen and phosphorus) to the subbasins 1995-2021

[9] “Earth beyond six of nine planetary boundaries” Katherine Richardson et al Science Advances 9, eadh2458 (2023).