Acidification and Arctic Haze - The Changing Arctic Environment: The Arctic Messenger - page 86

are mostly made up of small particulate matter (including aerosols) and acidifying pollut-
ants (anthropogenic sulphur and nitrogen oxides). The pollutants migrate towards the Arc-
tic in north-flowing air streams in the lower 5 kilometres and especially in the lower 2 kilo-
metres of the atmosphere. The lower-altitude streams mainly appear earlier in the winter
and originate from more northern mid-latitudes than the higher-altitude streams that appear
later and have travelled from more southerly sources. Once in the Arctic, they build up in
the high-pressure, stable Arctic air masses. These acidifying substances (mainly sulphate
and, to a lesser extent, nitrate) can therefore be deposited into the developing Arctic snow
pack, where they remain until released into the Arctic terrestrial and freshwater environ-
ments at the time of spring snowmelt.
For the first time, European and North American politicians were forced to recognize
that countries were producing atmospheric air pollution that crosses national boundaries.
Consequently, an impacted regional environment could be many hundreds of kilometres
distant from several different source regions that together were cumulatively responsible
for the observed environmental degradation. The only prospect for dealing with this com-
plex erosion of environmental quality was the development of legally binding national and
international environmental controls on emissions. This conclusion was not easily accep-
ted in some countries. For example, at the close of the administration of President Jimmy
Carter in 1980, it appeared that the United States was poised to take action on acid rain.
However, influential lobby groups vigorously opposed it. Indeed, it was not until the ad-
ministration of George H. W. Bush that concrete actions were introduced into the domestic
Clean Air Act. These were largely the same “denial” groups that will consistently appear in
the Arctic Messenger's story concerning persistent organic pollutants, stratospheric ozone
depletion and climate warming. The reference in the bibliography by Naomi Oreskes and
Erik Conway provides a good overview of how effective these groups can be when they
intervene in the political decision-making processes in North America.
As outlined in Part 2 of this story, countries decided to use the United Nations Eco-
nomic Commission for Europe (UNECE) to organise cooperative regulation of the sub-
stances responsible for acid rain. The UNECE includes not only Europe but also Russia