Environmental Engineering Reference
In-Depth Information
the case was added by the large-scale wild-land fires in Russia that started in the
middle of April and lasted up to the middle of May. These fires are not unusual
either - they take place nearly every year in western and central Russia. By end of
April the remnants of leaves and grass from the previous year dry sufficiently to
get burned. Due to limited fire fighting measures, once ignited, the fires can
continue during several days affecting large agriculture and wild-land areas. In
2006, the dry and warm weather prevailed in Western Russia during the
considered period, which particularly emboldened the fires. The third component
- anthropogenic pollution - concludes the list of sources of the episode. The
severity of the episode was a result of a combination of unfavorable atmospheric
conditions and intensive emissions from all the above source types ( Fig. 1) .
(b) Fire-induced PM 2.5 μg PM m −3
(c) Birch pollen grains m −3
(a) Anthropogenic PM 10 μg
PM m −3
Fig. 1. Concentrations of aerosols released from anthropogenic sources, wild-land fires and birch
forests, forecast valid for 1.5.2006, 6:00 UTC
4. Summary
With growing understanding of multi-dimensional character of the atmospheric
composition and air quality, it is important to include all the relevant species into
consideration while evaluating environmental or health consequences of the atom-
spheric pollution. Current setup of the SILAM modelling system allowed inclusion of
several main types of tropospheric aerosol and major reactive gases. The treat-
ments for the types of aerosol currently being under development are the wind-
blown mineral dust and secondary organic aerosol. The model applications showed
that most of the recent strong air pollution events have originated from more than
one source type, which are often synchronized and strengthened by unfavorable
meteorological conditions.
 
Search WWH ::




Custom Search