04 Oct 2018 Story Oceans & seas

Brainstorming towards a harmonized global methodology on eutrophication and plastic debris assessment

The Experts Workshop on Marine Pollution Indicators under Sustainable Development Goal Target 14.1.1, coordinated by UN Environment with the support of IOC-UNESCO, was held on the 12th-13th September, 2018, at UNESCO headquarters in Paris, France. The workshop brought together scientific experts and regional seas and earth observation specialists working on nutrient and plastics pollution in aquatic and marine ecosystems, with the ultimate goal of advancing a global methodology on eutrophication and plastic debris assessment under SDG target 14.1, ‘’By 2025, prevent and significantly reduce marine pollution of all kinds, in particular from land-based activities, including marine debris and nutrient pollution’.  

The meeting, which encouraged the flow of ideas through panel and open discussions rather than formal presentations sought to determine the state of science on marine pollution indicators, a systematic approach to assist countries in the adoption of a harmonized methodology, the frequency of reporting, the roles of various agencies in the development process, and the key elements of a global methodology. The meeting also sought to examine how to better integrate national and global data sources, and the potential applications of global data products in marine pollution assessment.  

In attendance, representing the efforts being made on assessment of marine pollution in the Northwest Pacific region was Genki Terauchi, a senior researcher at the Special Monitoring & Coastal Environmental Assessment Regional Activity Centre (CEARAC). CEARAC developed their own Procedures for Assessment of Eutrophication Status Including the Evaluation of Land-Based Sources of Nutrients for the NOWPAP Region or ‘NOWPAP Common Procedures’ in 2009. The NOWPAP common procedure consists of two steps: a screening procedure - applied to identify potential eutrophic zones by detecting symptoms of eutrophication using selected parameters; and a comprehensive procedure - which uses four categories of parameters, including the degree of nutrient enrichment, to assess the status and possible causes of eutrophication in the identified zones.  

CEARAC has been making efforts - using remote sensing - to prepare long-term, consistent chlorophyll-a data sets to be used for the screening procedures described above. During the meeting, Terauchi discussed the importance of assessing eutrophication in the long-term, particularly because not a lot of methodologies are taking into account that eutrophication isn’t just about nutrient pollution, it’s also a process that occurs naturally over geological time. In addition to this, Terauchi briefed participants on NOWPAPs current research regarding eutrophication, which combines chlorophyll-a threshold analysis with trend analysis in the long-term, and the essential role of combining data from multiple satellite sensors in this regard.

UNEP

Amongst what was concluded at the meeting was a general agreement that reporting on the relevant marine pollution be conducted at most annually - for satellite derived products, less frequently for measurements; the usefulness of dividing indicators into the groups ‘core indicators’ and ‘desirable/aspirational indicators’, with satellite derived chlorophyll a coming first on the list of core parameter indicators; and that countries or regional seas can take the role of providing locally measured indicators directly to UNEP.   Given that the process of mapping out a global methodology on eutrophication will require, at least, in the medium-term, the sustained engagement of collaborators - participants, and those experts that were not available to attend the meeting were encouraged to maintain interaction and remain available as a contact group.