Regional Ozone - Gdansk

Initial reference scenario   Figure A.11. Number of days with 8hour running average ozone concentration exceeding 120µg/m3 (IND120), calculated by the OFIS model, for a 150x150km2 area surrounding Gdansk, and wind rose of prevailing wind during the summer semester of 1999 (final reference scenario). Few days of exceedances were observed for the area of Gdansk. As shown in Fig. A11, these days are characterized by SE winds and high ozone concentrations mainly above the urban area. Although there is a considerable occurrence of NW winds and SW winds, no ozone plume is formed downwind of the city during the corresponding days. Very low emission estimations for urban NOx and no emissions for VOC at all, combined with zero boundary concentrations for ozone and VOC, resulted in limited production of radicals which would interfere to the NO-NO2-O3 reaction chain to favour ozone production. The small number of exceedances for most of the area is due to the absence of VOC in the studied area. The high urban ozone levels occur in the days of SE winds, as the pollution of air masses moving downwind of the city indicate in Fig. 2. This happens also due to the scarcity of the emission data available; there are no NO ground emissions for the urban area or the SE neighbouring cities of Elblag and Tczew to “consume” ozone that NO2 – emitted in considerable amounts from these two cities – photolysis produces. NW to Gdansk, in Gdynia and Sopot, comparable amounts of NO2 are emitted, but ozone production is counterbalanced by NO emissions, which, for these two cities, are available. As a final check, comparisons were made between the results presented here and the results that were made available from the GEA report (de Leeuw et al., 2001). Thus, it should be noted that the exceedances calculated in the GEA report for Gdansk, and the relev???ant emissions, were the same with the ones of the SUTRA reference scenario.   The indicators resulting for this scenario are as follows:     AOT(max), AOT(ave), AOT(sub), AOT(town) AOT60 176.04 26.55 76.35 105.78   IND120(domain) IND120(sub) IND120(town)   DAYS 9 28 39     Final reference scenario   The final reference scenario is the same with the initial one, as no updated emission or meteorology data were provided for the latter. Scenario S1   Figure A.12. Number of days with 8hour running average ozone concentration exceeding 120µg/m3 (IND120), calculated by the OFIS model, for a 150x150km2 area surrounding Gdansk. The indicators resulting for this scenario are as follows:     AOT(max), AOT(ave), AOT(sub), AOT(town) AOT60 175.39 26.45 76.09 105.42   IND120(domain) IND120(sub) IND120(town)   DAYS 9 28 39     «New Statistics»for Ozone ??? ST ave_ofis aot_ofis ind_ofis 1 10.64 0.11 2 2 18.73 24.04 9 3 47.33 107.61 36 4 18.63 25.2 10 5 68.61 146.96 48 6 16.78 18.69 10 7 61.53 156.23 36 8 20.18 30.1 9 9 10.75 0.11 2 Scenario S2 Figure A.13. Number of days with 8hour running average ozone concentration exceeding 120µg/m3 (IND120), calculated by the OFIS model, for a 150x150km2 area surrounding Gdansk. The indicators resulting for this scenario are as follows:     AOT(max), AOT(ave), AOT(sub), AOT(town) AOT60 175.36 26.45 76.09 105.43   IND120(domain) IND120(sub) IND120(town)   DAYS 9 28 39     «New Statistics»for Ozone ST ave_ofis aot_ofis ind_ofis 1 10.47 0.11 2 2 18.64 24.09??? 9 3 47.3 107.55 36 4 18.58 25.2 10 5 68.78 146.97 48 6 16.72 18.69 10 7 61.5 156.18 36 8 20.11 30.18 9 9 10.66 0.11 2 . Scenario S3   Figure A.14. Number of days with 8hour running average ozone concentration exceeding 120µg/m3 (IND120), calculated by the OFIS model, for a 150x150km2 area surrounding Gdansk. The indicators resulting for this scenario are as follows:   ???   AOT(max), AOT(ave), AOT(sub), AOT(town) AOT60 175.29 26.43 76.03 105.34   IND12???0(domain) IND120(sub) IND120(town)   DAYS 9 28 39     «New Statistics»for Ozone ST ave_ofis aot_ofis ind_ofis 1 10.28 0.12 2 2 18.56 24.03 9 3 47.24 107.5 36 4 18.5 25.2 10 5 69.82 146.86 48 6 16.64 18.69 10 7 61.46 156.14 36 8 20.09 30.1 9 9 10.48 0.12 2 Scenario S4   Figure A.15. Number of days with 8hour running average ozone concentration exceeding 120µg/m3 (IND120), calculated by the OFIS model, for a 150x150km2 area surrounding Gdansk. The indicators resulting for this scenario are as follows:     AOT(max), AOT(ave), AOT(sub), AOT(town) AOT60 175.27 26.42 76.04 105.35   IND120(domain) IND120(sub) IND120(town)   DAYS 9 28 39     «New Statistics»for Ozone ST ave_ofis aot_ofis ind_ofis 1 10.18 0.12 2 2 18.5 24.05 9 3 47.23 107.47 36 4 18.45 25.16 10 5 70.27 146.85 48 6 16.56 18.65 10 7 61.53 156.1 36 8 20.03 30.12 9 9 10.38 0.12 2 Scenario S5   Figure A.16. Number of days with 8hour running average ozone concentration exceeding 120µg/m3 (IND120), calculated by the OFIS model, for a 150x150km2 area surrounding Gdansk. The indicators resulting for this scenario are as follows:     AOT(max), AOT(ave), AOT(sub), AOT(town) AOT60 175.34 26.43 76.07 105.41   IND120(domain) IND120(sub) IND120(town)   DAYS 9 28 39     «New Statistics»for Ozone ST ave_ofis aot_ofis ind_ofis 1 10.13 0.12 2 2 18.47 24.06 9 3 47.33 107.58 36 4 18.43 25.16 10 5 70.92 146.99 48 6 16.54 18.66 10 7 61.68 156.23 36 8 19.99 30.13 9 9 10.34 0.12 2   Scenario summary The next figure provides with an overall summary of the indicators vs scenarios for Gdansk, indicating that the scenario performance is identical.     Figure A.17. Overall summary of the indicators vs scenarios for Gdansk. The same conclusion is supported by the next three diagrams (Figure A.18) concerning the “new statistics” introduced. A slight difference at the city centre is attributed to the urban NO emissions influencing the Ozone concentrations. Figure A.18 Receptors (x axis) and indicator values (y axis) f???or the Gdansk scenarios.

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