Chemistry Reference
In-Depth Information
100
90
80
70
60
50
30
35
40
45
50
55
60
65
70
75
80
Latitude, degrees N
Fig. 2 Decadal average maximum 8-h mean ozone levels along a north-south transect through
central Europe
Germany and BE0035R Vezin in Belgium. Together these eight stations provide a
picture of an “ozone maximum region” encompassing Belgium, Germany,
Switzerland, Italy and Slovenia in the heart of Europe. Surrounding this “ozone
maximum region”, there are further 25 stations with decadal averages in the range
from 80.3 to 86.2 ppb. These stations are located additionally in Austria, France,
Poland, United Kingdom, Netherlands, Spain and the Czech Republic. They, together,
provide a ring of countries surrounding the “ozone maximum region”.
Decadal averages are lowest, 55 ppb, at the NO0042G station Zeppelinfjell on
Spitzbergen in the Arctic. Even at this most remote European station, decadal
average maximum 8-h average ozone levels exceed the 50 ppb WHO air quality
guideline for ozone. There are 16 stations with decadal averages in the range
61.8-68.8 ppb. These include two stations in the United Kingdom: GB0033R
Bush and GB0002R Eskdalemuir, both in Scotland; the station CH0001G
Jungfraujoch in Switzerland which at 3,578 m is the highest altitude station in the
EMEP monitoring network; two Swedish stations SE0035R Vindeln and ES0013R
Esrange, both in northern Sweden; the Mace Head, Ireland station IE0031R on the
North Atlantic Ocean coastline; six stations in Norway, one station in Spain and
three stations in Finland.
Figure
2
constructs a north-south transect through the decadal averages in
Table
1
by plotting them out against station latitude. The plot uses only those
stations that are east of the Greenwich meridian and also excludes the high-altitude
alpine station CH0001G. The points appear to fall within a curved area with a
tendency towards higher decadal averages towards the south of Europe and lower
