Model assessment of B(a)P pollution: results for new EMEP grid and preliminary analysis for Spain Alexey Gusev, Victor Shatalov, Olga Rozovskaya, Nadejda Vulyh Meteorological Synthesizing Centre - East

Introduction Special session of Steering Body to EMEP (2016) on B(a)P and Wood burning - uncertainties of emissions factors, - PAH pollution levels and trends, - contribution of residential wood combustion and biomass burning (AIRUSE project) Spatial and temporal trends of B(a)P pollution - updated information on emissions and observed concentrations Progress in evaluation of B(a)P pollution - transition of modelling to the New EMEP grid Case study on B(a)P pollution in Spain - preliminary results

Observed B(a)P concentrations in EMEP region (2005-2014) Observed B(a)P concentrations indicate stabilization of pollution levels in recent decade In 2014 at 33% of stations annual mean B(a)P air concentrations were above the EU target level 1 ng/m3 2.5 -3 2.0 1.5 BaP in air, ng m 1.0 EU target level EU target level 0.5 0.0 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 Mean levels of B(a)P in air measured at background, suburban, and urban sites EEA AirBase measurements of B(a)P for 2014

PAH emissions in the EMEP countries (2005-2015) PAH emissions by sectors Largest contribution from Residential combustion Most of sectors show decrease (9% - 36%) Emission from Residential combustion is almost stable % change from 2005 to 2015 Italy 56 % Hungary 32 % Germany 9 % Romania 5 % Poland -18 % Five countries with largest emissions from Residential combustion sector

Progress in model assessment of B(a)P pollution: transition to the New EMEP grid New EMEP grid (0.2°x0.2°) Modelled vs measured BaP concentrations at background EMEP sites (2014) Old EMEP grid (50x50km) Old grid New grid Bias -20 % -5 % Correlation 0.73

Model assessment of B(a)P pollution in Spain: comparison with national measurements New EMEP grid (0.2°x0.2°) Modelled B(a)P concentrations vs. data of national and EMEP sites in Spain (2014) Overprediction EMEP sites National sites EMEP sites For some of the sites in Spain the model overestimate observed B(a)P concentrations

Case study on B(a)P pollution in Spain Case study for B(a)P was recommended by the recent Steering Body to EMEP Objective: Analysis of B(a)P pollution levels in Spain using EMEP fine resolution modelling and national data (measurements and modelling results) Country-specific study activities Modelling using national emissions and scenarios Verification of modelling results with EMEP and national measurements Analysis of pollution levels using GLEMOS and CHIMERE modelling results Sector-specific and source-receptor modelling using national emissions Data for the analysis National emissions with 0.1x0.1 resolution (2013, 2014) National measurements of B(a)P, EBAS, AirBase Modelling results of EMEP GLEMOS and CHIMERE models

PAH emissions in Spain: recent inventories National inventories of 2015, 2016, and 2017 Sectoral distribution (GNFR) Temporal coverage: 1990-2015 No speciation PAH emissions B(a)P emissions: fraction B(a)P/4PAHs is based on emissions of other EMEP countries Spatial distribution of annual B(a)P emission fluxes (0.1°x0.1°), g/km2/y Sectoral PAH emissions in Spain: sector L ~ 70%

Residential combustion (C) Spatial distribution of B(a)P emissions of Spain (2014): key source categories Agriculture (L) Industry (B) Emissions from field burning of agricultural residues dominate in southern areas Residential combustion (C) Road Transport (F)

Monitoring of PAH pollution levels in Spain Monitoring network for B(a)P: about 150 sites for period 2005-2016 Type of sites: background, suburban, urban, traffic, industrial Measured B(a)P concentrations do not indicate elevated levels in southern areas Locations of B(a)P monitoring sites (2014) Spatial distribution of annual B(a)P emission fluxes (0.1°x0.1°), g/km2/yr background rural background suburban background urban industrial traffic

PAH emission data versus measured air concentrations Annual PAH emission flux Spatial distribution of annual B(a)P emission fluxes in EMEP region, g/km2/y (2014) Measured B(a)P concentrations (2013, EEA AirBase) Average emission flux is among highest Observed B(a)P concentrations are among lowest

Model runs with varying contribution of emissions from agriculture Scenarios of B(a)P emissions for model simulations Base case: official emission data for 2014 Scenario 1: sector L decreased 2-fold (lower value of em. factor, EEA GuideBook) Scenario 2: sector L decreased 20-fold (average % in emissions of other EMEP countries) Base case Scenario 1 Scenario 2

Model evaluation of B(a)P pollution in Spain (2014) Setup of model simulations Meteorological data for modelling: generated using WRF for 2014 PAH emissions (incl B(a)P): for 2014 (spatial distribution based on 2013) Two nested domains: EMEP region, fine resolution domain over Spain (0.1°x0.1°) Boundary conditions: generated using modelling over EMEP region Modelled B(a)P air concentrations in the EMEP region and in Spain for 2014, base case model run

Model runs with varying contribution of emissions from agriculture Base case Scenario 1 Scenario 2 Assumption of lower emissions from agriculture (L) results in lower bias and higher correlation with measurements

Modelling results against measurements of background monitoring sites Results of model run with decreased emission from agriculture (Scenario 2) Modelled and observed B(a)P air concentrations (2014) Months Seasonal variations of B(a)P concentrations

Modelling results against measurements of background monitoring sites Results of model run with decreased emission from agriculture (Scenario 2) Modelled and observed B(a)P air concentrations (2014) Months Seasonal variations of B(a)P concentrations

Modelling results against measurements of background monitoring sites Area with significant disagreement between observed and modelled B(a)P air concentrations in North-eastern part of Spain Modelled and observed B(a)P air concentrations for 2014, (Scenario 2)

Modelling results against measurements of background monitoring sites Area with significant disagreement between observed and modelled B(a)P air concentrations in North-eastern part of Spain Overestimation in Barcelona Underestimation in mountainous areas Modelled and observed B(a)P air concentrations for 2014, (Scenario 2)

Emission from Residential Combustion vs observed B(a)P concentrations B(a)P pollution levels in North-eastern Spain: possible reasons of disagreement 1. Uncertainties in spatial distribution of emissions Negative correlation between measurements and total emissions as well as emissions from Residential Combustion Larger emissions from Res. Combustion are likely occurred in rural areas rather than in Barcelona urban area (Viana et al., 2016; EEA Report) Emission from Residential Combustion vs observed B(a)P concentrations

Original and modified spatial allocation of B(a)P emission fluxes B(a)P pollution levels in North-eastern Spain: possible reasons of disagreement 1. Uncertainties in spatial distribution of emissions Larger emissions from Res. Combustion are likely occurred in rural areas rather than in Barcelona urban area (Viana et al., 2016; EEA Report) Experimental scenario with modified spatial allocation for sector C (Res.Comb.) Original and modified spatial allocation of B(a)P emission fluxes

Modelled and observed B(a)P air concentrations, 2014 B(a)P pollution levels in North-eastern Spain: possible reasons of disagreement 1. Uncertainties in spatial distribution of emissions Larger emissions from Res. Combustion are likely occurred in rural areas rather than in Barcelona urban area (Viana et al., 2016; EEA Report) Experimental scenario with modified spatial allocation for sector C (Res.Comb.) Model simulations with altered spatial distribution of sector C (Res.Comb.) result in better agreement with measurements in Barcelona Modelled and observed B(a)P air concentrations, 2014

Modelled and observed B(a)P air concentrations, 2014 B(a)P pollution levels in North-eastern Spain: possible reasons of disagreement 2. Uncertainties due to modelling approach Insufficient spatial resolution Effects of specific meteorological and complex terrain conditions (inversions) may not were captured well Modelled and observed B(a)P air concentrations, 2014 Further analysis using refined emissions and finer spatial resolution is needed

Concluding remarks and further activity Modelling with emission scenarios indicated possible uncertainties in PAH emission data of Spain Refinement of PAH/BaP emissions of Spain is appreciated in co-operation with national experts and CEIP/TFEIP It is planned to perform analysis of factors affecting modelling results on B(a)P: parameters of degradation and deposition processes Evaluation of pollution using GLEMOS and CHIMERE modelling results Analysis of modelling results using measurements of B(a)P air concentrations for episodes, concentrations in vegetation, source apportionment studies, etc. Model evaluation of source-receptor relationships and contributions of individual sectors to B(a)P pollution Preparation of final report in co-operation with national experts and publication of results in peer-reviewed journal