The ENVIBASE-Project

Documentation / Online Handbook

Air Quality

Description of the Problem

Since 1976, Berlin has been identified as one of the thirty-four areas of (air) pollution according to the Federal Act for the Protection Against Emissions. In the last twenty years, the main problems of air pollution were caused by the comparatively high concentration of sulphur dioxide and dust, the two main components of winter smog. In 1980 the limit value of 80 µg SO₂/m³ (50 %ile 80/779/EEC) was exceeded over an area of about 100 km² in the inner city. In 1985 the limit value of 350 µg dust/m³ (95 %ile 80/779 EEC) was exceeded over almost the complete area of Berlin.

At that time, a monitoring network was set up as one basic part of the "Clean Air Plan." Analysis of air quality measurements today show that, in general, the air is getting cleaner. This is particularly evident in the case of sulphur dioxide: levels of this chemical have fallen to 1/3 of the 1976 values. This favourable situation was achieved mainly as a result of technical improvements in the western part of the city: modernisation of old houses which had previously burned mostly coal, a switch to coal with lower sulphur, and the installation of filters in power stations. From 1989 onwards, these measures were also implemented in East Berlin, but it should also be taken into consideration that many factories and plants were closed because of economic reasons. So in 1995, total domestic fuel emissions in the eastern part of Berlin lay just under 13 % of the 1989 level.

In contrast to the situation with sulphur dioxide and dust, developments in those fields where traffic is the main polluter have not yet reached a satisfactory stage. For nitrogen oxides (NO_x) no significant reductions have been achieved over the last few years. The success in the power station and heating sector has been balanced out by negative developments in the traffic sector. This also has an influence on the level of near ground ozone (summer-smog), which is created, significantly, from nitrogen oxides and hydrocarbons under very sunny conditions and is also transported to Berlin over long distances. Every year, depending on the meteorological conditions, the ceilings, laid down in the EU guidelines, were reached or exceeded.

Improvements to air quality with regard to SO₂ or dust also have positive effects on the living conditions of indicator organisms (such as lichen). The level of damage to temporarily exposed lichen has fallen dramatically. But many sections of our environment, like the forests, continue, nevertheless, to be damaged by the absorption of substances in the air. Regarding the critical levels laid down in the Geneva Clean Air Agreement of the UN ECE, it is obvious that the problem of emissions for the forests and other sensitive ecosystems remains considerable.

In addition to this interest in air quality and the classic pollutants, there has been new interest in the last few years in the emission of CO₂ resulting from energy consumption. CO₂, which is not classified as a pollutant in emission protection legislation or ordinances, thus occupies a central role in the so-called "greenhouse effect." There is no other possibility to reduce CO₂ than by a climate-oriented renewal in the energy sector. For the first time in Germany, the Environmental Atlas will publish a database and a map showing the influences of all sectors belonging to the CO₂-emissions block by block: industry/service companies, private households, public buildings, and traffic. This map, primarily orientated according to the public’s increasing sensitivity to this matter, will be a suitable basis for the planned CO₂-Monitoring-Cataster.

With regard to the objective of sustainability, saving energy will be crucial in securing the future of a metropolitan area like Berlin, with demands to the following sectors:

• minimising the amount of electric power used;
• reconstruction of the public and private traffic networks;
• conversion of all plants to run on most environmentally friendly fuel;
• modernisation of power and heating plants;
• orientation of values/targets/limits, etc. to the most sensitive parts of the environment.

Data Sources

BLUME, Berlin’s air quality network, has guaranteed continuous air quality monitoring since 1975 to measure the air pollution for the licensing of plants according to the TA Luft (Technical Instruction of Air Quality Control)

• to identify sources of air pollution;
• to verify the effect of air pollution control and prevention;
• to register smog-situations in the frame of smog alert plans.

The network consists of measurement equipment placed in containers set up in a 4 km-grid according to the TA and connected via telephone to a central computer . There are additional measurements in streets and residential areas with high pollution. As of 1997 there are twenty-one containers with measuring devices for SO₂, NO and NO_x, CO, O₃, HC (hydrocarbons), and dust (PM 10). Thirty cheap, active 7-day samplers for the traffic-caused substances benzene and EC, completed by passive samplers for NOx are installed at street lamps.

A special project is concerned with the development and pilot application of concepts, processes, and software for a model-supported analysis and consulting system for atmospheric pollutant dispersion running on parallel computers. The analysis covers both so-called winter smog (a single pollutant component) and summer smog (chemical transformation of numerous components into ozone).

The analysis and assessment of the regional distribution of air pollutants and their short- and long-term impact on organisms and ecosystems is managed in the ecological monitoring programme with twenty-five to forty-eight measuring points in grid and continuous ecological observation at forest sites. The information is collected in a cadastre of ecological pollution effects.

Emission databases for the primary polluter groups industry, domestic heating and traffic, are maintained in order to provide a differentiated evaluation and elimination of the sources of emissions. All estimates and calculations have been compared to the energy balance in which the total fuel consumption for Berlin is recorded.

For special projects (e.g. the CO₂-emissions relating to the block-scale 1:50000), these data were evaluated using the methods and instruments of the Environmental Information System (UIS-Berlin).

Methods

The choice of methods depends on the type of themes and data, e.g. whether they are representative only for the measurement point, a local or more regional area. The data from the emission calculated at 1 x 1 km are presented both as colour grid as well as absolute value. At the wide area depiction of the measured pollution, national (TA-Luft) or EC limits were selected as class values for the delimitation of the highest class. They were compared to the reference values "annual mean" and 98%-value.

The interpolations of the isolines were performed manually. In addition, the respective values from the BLUME-measurement stations are presented, distinguished according to type of station.

Some themes are based on digital models like the calculated pollutions SO₂ and NO_x as well as the calculated ozone concentrations in the near ground atmosphere.

The complex of the CO₂-emissions is orientated to the block-system for the emissions caused by private household, industry, or public buildings respectively to the line structures of the main road-system for the emissions caused by traffic. In this case, information from other maps were used, summarised, or composed (city structure, population density).

The presentation of the floristic and vegetation mapping of the herbaceous layer is based on a national guideline (VDI 3799/1) and therefore comparable with other investigations in Germany showing the influences of the general air pollution. A grid is used for presenting the contaminations caused by important inorganic air pollution components such as sulphur, acidic gases, and heavy metals, a transect for those caused by organic pollutants.

Results and Uses

In the Berlin Environmental Atlas, maps for eight themes -- for different times -- have so far been published or will soon be published in a printed form for the air quality /energy sector. All of them are also available on the Inter- and Intranet, seven on CD-ROM. All methods and results are documented in detailed texts; the digital methods and proceedings are available in special databanks. In the digital versions for the block-scale maps "Predominant Heating Types," "Building Heating Supply Areas," and "CO₂-Emissions," the concrete data for each block are also available using a special function "Show Data".

With this information, the main pollutants of the atmosphere responsible for the greenhouse effect are named and the most heavily polluted areas are shown. The development over the years of SO₂, NO_x, and dust can be seen. The diagrams of the ozone model represent the various interdependencies between the generation and decomposition of O₃, either for the understanding of such difficult processes or for the provision of decision-making aids for town planning and smog management. The two previously mentioned functions of Berlin Environmental Atlas maps are also essential for CO₂ emissions. Although this is a world-wide problem and CO₂ is not one of the classic pollutants with a direct influence on human health, all city planning authorities, in cooperation with the public, must be involved in the process of reduction of CO₂ (in Berlin, by 2010 the CO₂ levels should be reduced to 25 % below the 1990 level).