1. ICP waters; use of data from EMEP …and some results Brit Lisa Skjelkvåle and Heleen de Wit Norwegian Institute for Water Research

2. ICP Waters: International cooperative programme on assessment and monitoring effects of air pollution on rivers and lakes Programme aims
Assess the degree and geographic extent of the impact of atmospheric pollution, in particular acidification, on surface waters
Collect information to evaluate dose/response relationships
Describe and evaluate long-term trends and variation in aquatic chemistry and biota attributable to atmospheric pollution

3. Surface water ecosystems

4. The recovery process Damage Recovery
(conceptual model by Posch et al.)
Simplified description of development of
acid deposition,
a lake chemical variable (ANC)
the corresponding biological response
Damage Recovery

5. Lake Saudlandsvatn in
Southern Norway

6. Observations L.Saudlandsv
Reference. Hestagen et al 2011, Sci Tot Environ

7. Ex-post deposition scenarios for L
Ex-post deposition scenarios for L.Saudlandsvatn Reference:WGE Joint report

8. Ex-post water chemistry scenarios for L
Ex-post water chemistry scenarios for L.Saudlandsvatn NAT – scenario MAGIC Reference: WGE Joint report

9. Exceedance of CL for acidification of surface waters in Norway using NAT, PRI and MFR scenarios
The calculated exceedance of critical loads for
acidification of surface waters, using the FAB model
(Reference:
Letter to KLIF, T. Larssen Dec 2010)

10. ICP Waters network Chemistry at all sites
Biology at selected sites and not in all countries

11. Trends in ANC 1990-1999 and 1999-2008 ICP Waters sites
All median trend slopes in all regions are positiv
Slightly lower increase than

12. Some reflections The aim of the effects work is to:
document the effects of decreases or increases in air pollution by monitoring sensitive parts of natural and seminatural ecosytems, health and materials
document need for further emission reductions
From ICP Waters reporting:
The consistent pattern of chemical recovery across a large number of sites is the strongest evidence that emission control programmes are effective. In many areas, water quality is now sufficient for the return of acid-sensitive aquatic biota.

13. ..and some more reflections
ICP Waters needs:
Measured precipitation chemistry for relating observed trends in water chemistry with observed precipitation chemistry
Historical S and N (and base cation) deposition for calibrating dynamic models
Future S and N deposition scenarios for calculating
possible water chemical responses
possible biological responses
exceedance of CL
Better cooperation EMEP - WGE;
define joint projects and publish results together

14. Thank you!