Developments in

Critical Loads and Dynamic Modelling

Maximilian Posch

Coordination Center for Effects (CCE)ICP Modelling & Mapping (ICP M&M)Working Group on Effects (WGE)

MNP, Bilthoven, The Netherlands

Update of CL and DM data in spring 2005:

2 calls for data:

1. CLs of heavy metals (Pb, Cd, Hg): - different criteria (ecosystem/health) - 18 NFCs responded - EMEP/MSC-E provided depositions/conc. (emission uncertainties!) - Health->agriculture->fertiliser inputs important - Pb more exceeded than Cd - use in review/revision of HM Protocol as yet undecided - CCE Report distributed; available on www

Update of CL and DM data in spring 2005 (2):

2. CLs of acidity & nutrient N and DynMod of acidity:

- 14/13 provided update (of 24 NFCs)- EMEP/MSC-W provided deposition data (also BC deposition!)- Overall, not many changes in CLs- DynMod clearly adds to complexity …- CCE Report being sent out; already available on www

Coverage:

Grid: CL data from NFCs – Green: Also DynMod – Red: Also Target Loads

Exceedance of acidity CLs (1):

Exceedance %: EU25: 17.9 11.0 7.0 4.1 3.7 3.4 1.8 Europe: 8.6 6.1 4.3 3.2 3.0 2.9 0.9

Exceedance of acidity CLs (2):

Exceedance %: EU25: 17.9 11.0 7.0 4.1 3.7 3.4 1.8 Europe: 8.6 6.1 4.3 3.2 3.0 2.9 0.9

Exceedance of eutrophication CLs (1):

Exceedance %: EU25: 65.2 60.4 55.9 45.7 40.9 38.6 24.6 Europe: 28.5 28.0 26.9 23.6 22.3 21.6 9.6

Exceedance of eutrophication CLs (2):

Exceedance %: EU25: 65.2 60.4 55.9 45.7 40.9 38.6 24.6 Europe: 28.5 28.0 26.9 23.6 22.3 21.6 9.6

Use to date (Gothenburg Protocol, NEC Directive):

- Within every 150x150 EMEP grid cell so-called (protection and) exceedance isolines were calculated by the CCE and provided to CIAM/TFIAM.- This is an approximation; and results in a large amount of data. Also, the implementation in optimization algorithms is non-trivial.

New challenges:

- 50x50 grid: number of grids 500 4,000- ecosystem-specific depositions (>= 3 per grid cell)

too many data and equations for optimisation …

The Use of CLs in Integrated Assessment (IA)i.e. how CL data are used by CIAM/TFIAM

KkEEafAAEAAEP

p

N

jjpjpjkpkk

p

,...1,1 1

,,,0..,0

AAEk is the AAE in receptor k for the new (or to be determined) emissions Ep,j of pollutant p in emitter area j;AAE0,k is the AAE for the reference emissions E0,p,j; Np is the number of emitter regions for pollutant p,P is the number of pollutants (P=3),f is a unit conversion factor, K is the number of receptor areas.ap,k,j are the coefficients – impact factors -- determining the linear model, characterising the ‘strength’ of the relationship between emissions of pollutant p in country j and AAE in region k.

… therefore new methodology:

Linearised relationship between AAE and emissions:

[Similar methodology used in Life Cycle Impact Assessment]

Graphical representation of impact coefficients for eutrophication:

Graphical representation of impact coefficients for acidity:

How good is the linear approximation? (1)

Country-to-country relationships (acidity & nutrient N):2 examples: BE NL and DE SE

SO2: red; NO2: green; NH3: blue

acidity

aciditynutrient N

nutrient N

How good is the linear approximation? (2)

(a) All countries GB(b) All countries to Europe

acidification: redeutrophication: green

Ongoing Work:

- Derive impact factors for Target Loads instead of CLs (exceedance non-attainment)

- Investigate how time information (RDT and DDT) can be used in IAM

More information:

CCE reports 2005: - Heavy Metals Report

- Status Report 2005

CCE website: www.mnp.nl/cce

Thank you for your attention!