Coherent geographic scales and aggregation rules in assessment and monitoring of Good Environmental Status Theo Prins, Myra van der Meulen, Arjen Boon (Deltares) Nomiki Simboura, Catherine Tsangaris (HCMR) Angel Borja, Iratxe Menchaca (AZTI) Alison Gilbert (IVM) 17 March 2014

Objectives Analyse and compare national approaches per descriptor regarding geographic scales Analyse which aggregation rules have been applied Develop broad EU guidance for coherent geographic scales in assessment and monitoring of GES and for sets of aggregation rules and organize a debate with MS on this. 23 October 2013

Main questions What is the appropriate spatial scale for the assessment of the marine environment? How to scale up assessment results from assessment areas to larger geographic scales? How to aggregate for a comprehensive status assessment indicators & criteria within a descriptor across descriptors 23 October 2013

descriptors GES criteria indicators Aggregation across asssessment levels Aggregation across spatial scales 23 October 2013

Draft report on guidance Analytical report Discussed with Drafting Group Sept 2013 Discussed in WG GES workshop Oct 2013 Final version November 2013 WG GES workshop October 2013 Results analysis Identification of key issues for guidance Draft report on guidance Comments by Drafting Group Feb 2013 February 2014 Final report April 2014 23 October 2013

Analytical report (Nov 2013) Analysis of MS approaches regarding spatial scales (based on electronic reporting) Large differences between MS in spatial scales for assessments 1 to >10 assessment areas <100 to >100,000 km2 Sometimes MS approaches differ between descriptors, but available information limited Analysis of MS approaches regarding aggregation rules (based on electronic reporting) MS mainly used existing assessment methods No aggregation across descriptors Limited comparability/coherence in approaches 23 October 2013

Guidance document Some introductory remarks: Report provides a comprehensive overview of options for spatial scaling and aggregation Not yet a final recommendation Still many open issues and knowledge gaps Need for practical testing of solutions 23 October 2013

Guidance document: spatial scales Definition of spatial assessment scales needs to consider Ecological characteristics (hydrodynamics, biogeography, etc.) Management perspective (pressures, information needs, etc.) High number of indicators and descriptors In principle, many options for deciding on scales, depending on the indicator or descriptor Balance between the ‘perfect’ approach that suits the characteristics of each indicator, and a manageable number of assessment areas “HELCOM approach” seems promising 23 October 2013

Guidance document: spatial scales HELCOM approach Nested, hierarchical levels Different levels of spatial resolution Fit different indicators/descriptors Already developed and used by HELCOM for biodiversity, eutrophication, contaminants Level 1 Level 2 Level 3 Level 4 Increased spatial scale of assessment areas 23 October 2013

Guidance document: spatial scales Next steps Develop and test this approach for other indicators/descriptors Need for more specific criteria for each descriptor? Develop and test this approach for other sea regions Coherence within and between regions Develop methods for aggregation/disaggregation (e.g. switch between national/subregional level) Level 1 Level 2 Level 3 Level 4 Increased spatial scale of assessment areas 23 October 2013

Guidance document: aggregation Aggregation of assessment results Aggregation inevitably leads to loss of information Information needs are different at different levels of aggregation MS Spatial scale Aggregation level metrics indicators criteria descriptors GES Monitoring sites Assessment units National waters (sub) region European seas RSC EU 23 October 2013

Guidance document: aggregation Rules for aggregation of indicators, criteria within descriptors: For some assessments there are already existing methods (for example: eutrophication, contaminants by OSPAR/HELCOM) Criteria for appropriate aggregation rule One-out all-out useful in some cases, e.g.: Precautionary principle Legal criteria Different pressures Wide variety of methods available as alternative for OOAO 23 October 2013

Guidance document: aggregation Rules for aggregation of indicators, criteria within descriptors: Discussion points, further work In what cases OOAO is needed, in what cases other methods are preferred Aggregation within biodiversity related descriptors how to combine different ecosystem components (functional groups, ecosystem structure, ecosystem function, habitats) 23 October 2013

Guidance document: aggregation Rules for aggregation across descriptors: Options: All descriptors achieve GES No weighting of descriptors Use of one-out all-out All descriptors and indicators must form a consistent assessment framework Various other options for combining descriptors, e.g. pressure descriptors <-> state descriptors Combine biodiversity descriptors (D1, D4, D6) Distinguish functional or species groups Other combinations of descriptors Apply different weights to various groups 23 October 2013

Guidance document: aggregation Rules for aggregation across descriptors: Discussion points, further work: Is aggregation / combination of descriptors desired? What kind of aggregation / combinations How to represent GES at an aggregated level? 23 October 2013

23 October 2013

Definition of assessment scales Step 1 Indicator assessments Aggregation across all descriptors in a (sub)region Step 2 Aggregation at descriptor level (or combinations) Step 3 Aggregation at (sub)region level Step 4