GAW Report No. 205 - IGAC Project

CHAPTER 6 - EUROPE• During the winter campaign, wood burning was a significant source of organic aerosol. Bothlocal emissions and continental advection were responsible for aerosol pollution build-up.6.3.6 Conclusion and outlookIn conclusion the Paris agglomeration is a major population hotspot with high pollutantemissions from traffic, the residential/tertiary sector, and industry. Good dispersive conditions limitthe impact on air quality of these emissions. With respect to valid air quality regulation (or valid innear future), NO 2 (annual mean) is the most critical pollutant, followed by fine particles and ozone.Several intense studies have allowed to draw a rather coherent picture of photo-oxidantpollution in the agglomeration and its plume, as well as a quantification of precursor emissions (NO X ,CO and VOC) and their respective impact on photo-oxidant levels. For particulate matter, theobservations, simulations, and source apportionment of carbonaceous aerosol is still uncertain tohighly uncertain. The recent MEGAPOLI campaign intends to close this knowledge gap. Detaileddata sets on aerosols and their radiative and hygroscopic properties from this campaign should alsohelp to better quantify the aerosol impact on regional climate in the region.6.4 MOSCOW6.4.1 Population, demographics, geography, and urban structureMoscow is the capital and the largest city of Russia. It is also the largest metropolitan area inEurope, and is the seventh largest megacity in the world. According to the 2002 census the Moscowpopulation was estimated at 10,382,754. However, this figure only takes into account legalresidents. Substantial numbers of internal migrants mean that Moscow's population is stillincreasing, whereas the population of many other Russian cities is in decline. The cityencompasses an area of 1035 km 2 . The Moscow River flows through the centre of the city and theKremlin lies in the direct centre. In Figure 16 the blue-gray pixels in this false-colour image areurban areas of Moscow. The light green areas surrounding the city are farms and the brown regionsare more sparsely vegetated areas. This image of Moscow was acquired by the EnhancedThematic Mapper plus (ETM+), flying aboard the Landsat 7 satellite on July 23, 2002. Averageelevation of the city is 156 m. The highest point is Teplostanskaya highland at 255 m. The lowestpoint, 110 m, is the Moscow river bank in the South-eastern part of the city. Green areas make up30% of the territory, which is a fairly high value for a megacity.Figure 16 - Left: Satellite image of Moscow acquired by the Enhanced Thematic Mapper plus (ETM+), flying aboard theLandsat 7 satellite. July 23, 2002 (NASA, http://visibleearth.nasa.gov/view_rec.php?id=3434)Right: Map of the Mosecomonitoring air pollution monitoring stations in Moscow and suburbs208