Trend analysis of nitrogen dioxide concentrations in Eastern Switzerland
At a glance
- Project leader : Dr. René Locher
- Project status : completed
- Funding partner : Public sector (excl. federal government) (OSTLUFT)
- Project partner : OSTLUFT
- Contact person : René Locher
Description
Nitrogen dioxide (NO2) is a component of air which, when too
high in concentration, causes harmful effects to plants,
over-fertilizes sensitive ecosystems, irritates eyes, respiratory
system and skin. In addition, NO2 and volatile organic compounds
form the educts that generate the pollutant ozone (O3). Therefore,
Swiss Confederation has defined thresholds for ambient
concentrations ??of NO2, which have to be continously
monitored.
The cantons of Zurich, Schaffhausen, Thurgau, St. Gallen, both
Appenzell, Glarus, Graubünden and the Principality of Liechtenstein
have joined forces in the organization "Ostluft" to monitor ambient
concentrations of air pollutants. In the area of Ostluft, NO2
passive samplers have been exposed at nearly 300 locations since up
to 30 years.
Ambient NO2 concentrations measured at a given location at a given
time depend primarily on the amount of nitrogen oxides emitted in
the surrounding area, the distance of the sources to the
measurement location and current weather conditions. Ambient
concentrations reflect the development of the direct effects of
nitrogen oxides on humans and environment. Since weather depends on
season and year of measurements and thus shows large variation over
time, ambient concentrations varies much more strongly within and
between years than variation of emissions suggests. For tracking
the evolution of local emissions, weather effects must therefore be
assessed and removed from the evolution of ambient
concentrations.
IDP was mandated by Ostluft to evaluate these extensive data. The
weather-adjusted evolution of NO2 concentrations was of particular
interest in order to draw conclusions about the success of the
measures introduced to reduce NO2 emissions in diesel and gasoline
vehicles, oil, gas and wood heating and combustion processes in
industry.