LINKING EUROPEAN, NATIONAL & CITY SCALES UK National Focal Centre for Integrated Assessment Modelling Helen ApSimon and Tim Oxley, Imperial College in collaboration with CEH, NETCEN and ENTEC

Since Gothenburg/NECD many improvements: e.g.: EMEP model-> 50x50 km Eulerian -> country-to- grid source receptor matrices NB ceilings do not dictate how or where countries change emissions- ASAM/RAINS assume uniform scaling in each Ecosystem dependent deposition + finer grid -> estimated exceedence of CLs increased Linking of European to global scale/climate questions

Large reductions SOx and NOx -> greater relative importance of NH 3 Now include particles- both primary and secondary NB both NHx deposition and PM concentrations are due to a mixture of local and transboundary sources  targeted action within a country -> greater improvements than uniform scaling  for “binding squares” local action in the home country may reduce effort required by other countries  capability for more detailed study of sub- areas/countries ??? additional measures at local scale

European scale: ASAM National scale: UKIAM Urban scale/air quality: USIAM (individual streets) Common Framework: List of sources+ cost-curves List of receptors e.g. ecosystems, people, crops + source-> receptor matrices Criteria for protection each receptor; e.g. AQ limit values, Critical loads Scenario analysis or optimisation- stepwise approach converging to targets.

Imported from Europe EMEP S-R matrices + ASAM tool EMBEDDING SUB-GRID UK sources S-R matrices from FRAME and PPM Shipping EMEP model + ASAM tool Hot-spots /roads ADMS

SOURCES EMISSION EXPOSURE EFFECTS/RECEPTORS Energy Agriculture Industry Traffic Sulphur dioxide Ammonia Nitrogen oxides VOCs Sulphur deposition Nitrogen deposition SO 2,SO 4 air concns NO 2,NO 3 air concns Ozone Acidification Eutrophication Human health Materials Yield losses Surface waters Terrestial ecosystems Marine ecosystems Crops Forests Domestic Particles Primary sources PM 10/2.5 UKIAMUKIAM NH 4 concn Air quality Criteria

EMEP model inter- comparison study with smaller scale models: Need to be consistent- e.g. imported/exported fluxes Model Dry Wet Total UKIAM EMEP 1 EMEP SOx dep

Based on CL data for UK from CEH Monkswood

For N deposition spatially targeted measures for NH 3 can bring much greater improvement than uniform scaling across the country.

NH 3 Cost Curve for Lancashire: MARACCAS model of NARSES project NARSES project- geographical analysis (10 km grid) Different types of farming, local conditions-> applicability of measures. Interaction with other problems- nitrate leaching (NVZs), N 2 O Generation of cost curves for localised areas for UKIAM At even smaller (field) scale other factors such as controlled zones or buffer strips between intense emissions and sensitive ecosystems could make a big difference

distance km NB EMEP assume 5% of S is emitted as SO 4 - equivalent to 650kt in EU+NMS compared with 2297 kt of primary PM 10

PPM 2 nd A 2 nd B

UKIAM ->maximise reduction in population exposure at least cost

£m Pop exp reducn g/m3 Reduction in population exposure v cost

In this example cost-curves were disaggregated to different sectors. Because of different geographical distributions and dispersion characteristics the relative contribution of different sectors to population exposure is not the same as the relative emissions. That is the reduction in population exposure per ton reduced is different for different sectors. The effect this has on selection of abatement measures can be investigated.

Future developments Further work on modelling and linking models; modelling of PM Extension to PM 2.5 Link to AQ legislation (and ? NO 2 ) Work on NH3 linked to NARSES Scenario analysis – e.g. linked to RAINS scenarios

Conclusions: More detailed studies of embedded regions/national scale can supplement RAINS/European modelling by i) exploring problems where both local and transboundary sources contribute and ii) investigating interaction between compliance with emission ceilings and other issues e.g. local air quality