GAW Report No. 205 - IGAC Project

CHAPTER 6 - EUROPEFigure 37 - Map of Greater Athens Area with altitude contours at 200 m intervals[Melas et al., 1995]6.7.3.2 Emissions of pollutants and their precursors in the areaThe massive number of registered vehicles in circulation (over 2.5 million, growing at a rateof 7% yearly) is allegedly the major cause of air pollution related problems in the area, taking intoaccount that a large proportion of these vehicles are non-catalytic (0.8 million) or are powered byold technology diesel engines (0.2 million). Although the use of natural gas for domestic heatingpurposes has increased lately, combustion of fuel oil is still primarily used for central heating.An anthropogenic emissions inventory was compiled for Greece and the Greater AthensArea (GAA) for the reference year 2003 [Markakis et al., 2010a; Markakis et al., 2010b] with a 10km spatial grid over Greece and a 2 km grid over GAA. The emission inventory has monthly, weekly,and hourly temporal analysis. Total annual emissions for the GAA were estimated to be 473 kt forCO, 78 kt for NO X , 31 kt for SO 2 , 93 kt for NMVOCs, and 20 kt for PM 10 . Approximately 75% of CO,70% of NMVOCs, and almost half of NO X emissions originate from the road transport sector whilethe most important SO 2 emitter is the industrial sector. The majority of PM emissions stem from theindustrial sector. The large industrial complexes are located several kilometres outside the Athensbasin where the majority of the population resides. Inside the basin the road transport is again themost important emission source for PM. Almost 20% of PM emissions originate from non-exhaustsources like tire and break wear as well as road abrasion. The annual variation of emissions showsthat although the central heating operations do not account for more than a few percent in theannual totals (with an exception of SO 2 – 15% contribution), in the winter months they make asignificant contribution. According to Greek national totals Athens is responsible for almost half ofthe road transport sector CO emissions and 70% of the NO X emissions. Taking into account thatalmost half of the county’s population inhabits the GAA as well as the fact that Athens experiencesvery severe congestion with the average speed not to exceed 12 km/h during rush hours, the resultsare not surprising.6.7.3.3 Air pollution levels and abatement measuresThe GAA has been subject of intensive field campaigns like MECAPHOT-TRACE in summer1994 [Ziomas, 1998 and references therein] and PAUR I and II [in summer 1996; Zerefos et al.,2000 references therein]. For the GAA, the air quality reports have showed that there has been agreat improvement in the latest years regarding the pollution levels. This is mostly due the fact thatthe large industries were reallocated from inside the Athens basin to the greater area while more239