352
Z. Ferenczi et al.
factors that play important roles in PM concentration reduction strategies. Analysis
of local and regional meteorology is important to completely understand the processes responsible for the spatial and temporal distribution of PM in all geographic
regions [1, 4].
In Hungary, one key issue in air quality research is to find the sources and the
influencing meteorological factors for aerosol particles, which cause elevated levels
of particulate matter concentrations in the Carpathian Basin. Although the quality
of the emission databases have been improved in the latest years in Europe, the
determination of the quantitative contributions of different sources (e.g. domestic
heating and automobile exhaust) to PM 10 and PM 2.5 concentrations remains a difficult
task. The difficulty is not only due to the uncertainties in the emission data, we do not
have an accurate knowledge about how the meteorological situations influence the air
pollutant levels either. These two facts may result in the air quality forecasts for this
region not always being successful, especially in the case of particulate matter. The
situation is further complicated by the fact that PM can not only be emitted directly
but it can also form in the atmosphere when gaseous pollutants (SO 2 and NO x )
undergo transformation to form secondary inorganic particles [2]. This complexity
demonstrates, that meteorology plays a key issue in the air pollution analyses. This
is also the reason why the smog situations have to be examined in depth in Hungary.
56.2 A Special Meteorological Situation in Hungary: The
Cold Air Cushion
The cold air cushion is a special meteorological situation that is related to inversion
in the upper atmosphere. It most frequently evolves in areas that are surrounded by
chains of mountains. Anticyclonic events trigger the development of cold air cushions
as they foster downward motions in the air. By serving as a barrier for mixing motions,
inversion causes the air to stabilize and it hinders the movement of the air mass out
of the basin. This effect is enhanced by the presence of the surrounding mountains.
A meteorological situation like the cold air cushion has environmental consequences. The lack of mixing processes, together with the increased rate of emission
caused by residential combustion, due to the cold, pollutants of anthropogenic origin accumulate rapidly. Concentrations of pollutants in the air can easily reach and
exceed levels that are considered harmful for the health.
56.3 Influence of Meteorological Parameters on PM 10
Such an anticyclonic situation occurred at the end of January 2017 in the Carpathian
Basin, which caused temperatures in the Sajó Valley, located in the north-eastern part
of Hungary, to drop well below −10 °C for a period of time covering the last days of
Z. Ferenczi et al.
factors that play important roles in PM concentration reduction strategies. Analysis
of local and regional meteorology is important to completely understand the processes responsible for the spatial and temporal distribution of PM in all geographic
regions [1, 4].
In Hungary, one key issue in air quality research is to find the sources and the
influencing meteorological factors for aerosol particles, which cause elevated levels
of particulate matter concentrations in the Carpathian Basin. Although the quality
of the emission databases have been improved in the latest years in Europe, the
determination of the quantitative contributions of different sources (e.g. domestic
heating and automobile exhaust) to PM 10 and PM 2.5 concentrations remains a difficult
task. The difficulty is not only due to the uncertainties in the emission data, we do not
have an accurate knowledge about how the meteorological situations influence the air
pollutant levels either. These two facts may result in the air quality forecasts for this
region not always being successful, especially in the case of particulate matter. The
situation is further complicated by the fact that PM can not only be emitted directly
but it can also form in the atmosphere when gaseous pollutants (SO 2 and NO x )
undergo transformation to form secondary inorganic particles [2]. This complexity
demonstrates, that meteorology plays a key issue in the air pollution analyses. This
is also the reason why the smog situations have to be examined in depth in Hungary.
56.2 A Special Meteorological Situation in Hungary: The
Cold Air Cushion
The cold air cushion is a special meteorological situation that is related to inversion
in the upper atmosphere. It most frequently evolves in areas that are surrounded by
chains of mountains. Anticyclonic events trigger the development of cold air cushions
as they foster downward motions in the air. By serving as a barrier for mixing motions,
inversion causes the air to stabilize and it hinders the movement of the air mass out
of the basin. This effect is enhanced by the presence of the surrounding mountains.
A meteorological situation like the cold air cushion has environmental consequences. The lack of mixing processes, together with the increased rate of emission
caused by residential combustion, due to the cold, pollutants of anthropogenic origin accumulate rapidly. Concentrations of pollutants in the air can easily reach and
exceed levels that are considered harmful for the health.
56.3 Influence of Meteorological Parameters on PM 10
Such an anticyclonic situation occurred at the end of January 2017 in the Carpathian
Basin, which caused temperatures in the Sajó Valley, located in the north-eastern part
of Hungary, to drop well below −10 °C for a period of time covering the last days of