1. 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

2. 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

3. 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

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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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

12. 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

13. 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

14. 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

15. 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

16. 23 October 2013

17. 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