184
N. F. Elansky
the aid of powerful short-wave radiation. Such experiments were carried out using
the “Sura” heating stand [
Kulikov et al., 2012; Kulikov et al. 2013; Kulikov and
Frolov, 2013]. The radiation power amounted to 100 MW. Ozone-layer distur‑
bances at heights of 50–90 km were measured using the method of ground-based
microwave radiometry. On the basis of the results obtained in these experiments,
a new physical phenomenon was revealed — the intensity of the microwave ra‑
diation of the mesosphere within the ozone line decreases when the ionosphere
changes its state under the influence of powerful short-wave radiation.
Observational VOD data obtained with the SBUV/SBUV2 satellite instru‑
ments in 1978–2003 were used to estimate the effect of the 11-year cycle of
solar activity on the content of ozone in the stratosphere and mesosphere [
Gru-
zdev, 2014a]. A high coherence was revealed between the content of ozone and
the level of solar activity on the solar-cycle scale. Maximum heights for the
sensitivity of ozone to the 11-year cycle of solar activity were noted for the upper
(50–55 km), middle (35–40 km), and lower (below 25 km) stratospheres. Max‑
imum variations (up to 10%) in the content of ozone were noted for spring and
summer in the polar regions. The content of NO
2
in the stratosphere also varies
under the influence of the 11-year cycle of solar activity [
Schmidt et al., 2013].
There are interhemispheric differences in its variations (up to the change of sign).
These variations do not exceed 5%. Taking into consideration the 11-year cycle
made it possible to specify the effect of the Pinatubo eruption products on ozone
and NO
2
[
Gruzdev, 2014b]. In the response of ozone, there are two layers with
its decreased concentration: 25–32 km within the latitudinal zone 50
o
S‑40
o
N
and 18–25 km within higher latitudes in both hemispheres. A maximum 22%
decrease in the concentration of ozone was observed at heights of about 32 km
within 10
o
‑15
o
S. The decrease in the content of NO
2
amounted to 23–33% in the
middle latitudes.
The influence of the subtropical jet stream (SJS) on the VOD is estimated in
[
Bukin et al., 2011]. Data obtained from lidar sounding along the meridian of
longitude 132
o
E, which crosses the SJS active region, were also analyzed. The
VOD is locally maximum above the tropopause in the upper tropopause inversion
layer and the VOD is minimum in the lower stratosphere. It is assumed that the
local maximum and the inversion layer are formed due to the superposition of the
stratospheric and tropospheric cells of circulation in the vicinity of the SJS axis.
2.3. Numerical simulation
A method for calculating the atmospheric emissions
of ozone precursors from
natural fires has been developed for three-dimensional chemical transport models
[
Konovalov et al., 2011; Berezin et al., 2013; Berezin et al., 2013]. The key
185
Ozone
features of this method are the use of daily maxima of the intensity of IR radia‑
tion from fires according to satellite data and the assimilation (by such a model)
of ground-based measurement data on atmospheric pollution. This method has
successfully been tested in comparing model data on the composition of the at‑
mosphere over Russia with data obtained from ground-based and satellite meas‑
urements. The model study of the evolution of ozone and its precursors in Rus‑
sian regions with natural fires in summer 2010 has been conducted [
Konovalov
et al., 2012]. A current chemical transport model and the developed method for
calculating the amount of pollutants emitted by fires were used. It was revealed
that an increase in the rate of the formation of ozone in a smoke plume, which is
caused by increased concentrations of
its precursors,
is fully compensated due
to the fact that the flux of solar radiation is attenuated by smoke aerosol [
Berez-
in et al., 2013]. It was first shown that heterogenic reactions on the surface of
smoke aerosol may result in significant ozone losses in the atmospheric surface
layer [
Konovalov et al., 2012].
The model study of the transboundary transport of anthropogenic pollutants
from China to the Far East region of Russia has been conducted [
Kuznetsova et
al., 2013]. It was found that the transboundary transport of anthropogenic pol‑
lutants may cause repetitive events with increased O
3
and NO
x
concentrations in
the atmosphere over southern Khabarovsk krai. The results of both trajectory and
synoptic analyses showed that the occurrence of such events is caused mainly by
the transport of air masses from north‑eastern China in the forepart of continen‑
tal cyclones [
Kuznetsova et al., 2013].
The distribution of the concentrations of ozone and its precursors (CO and
NO
x
) over Siberia was numerically simulated using the GEOS-chem global
transport model [
Shtabkin and Moiseenko, 2014]. The results of this simulation
adequately reproduce the measured (in Zotino) concentrations of these gases, and
this favors the view that the photochemical system in the boreal zone of Eurasia
is homogeneous [
Heimann et al., 2014; Engvall Stjernberg A.-C. et al., 2012].
Natural fires significantly contribute to the tropospheric content of ozone, and
their contribution dominates over that made by both long-range and regional
transports of anthropogenic pollutants.
The air quality has been estimated and predicted for the Moscow region using
both WRF ARW and CHIMERE models [
Zaripov et al., 2011]. Different configu‑
rations of the prediction system, which differ in spatial resolution and a method of
specifying boundary conditions, have been considered. An empirical model for pre‑
dicting the daily mean concentrations of ozone on the basis of a neural net has been
developed for the Tomsk region [
Аntokhin et al., 2013b]. The neuronet approach
has proved more efficient when compared to models based on multiple linear re‑
gression and autoregression. This approach makes it possible to describe up to 70%
of the total variance of mean value and 50% of the variance of rms deviation.