Analysis of long-term air quality trends and variations in Northern Europe

Air concentrations of Pb-210 and particle bound sulphur, which are both secondary aerosol tracers, were used in this study to depict air quality. Long-term variations of air quality in Northern Europe were found to be closely related to the surface conditions of the Nordic Seas. For example, the amount of warm saline Atlantic water in the North Sea almost invariably governs air quality climate in the Nordic Countries to a degree that makes long-term forecasting possible. Any prompt correlation between climate and sunspot cycle appears to be illogical, because the weather forcing mechanism must work through slowly acting processes in the Nordic Seas. It is, however, possible that interactions between two climate change-triggering mechanisms based on sound principles may act in the direction of synchronising the pendular motion of climate with the variable activity of the sun. When the warm Gulf stream meets the arctic air mass in winter, the raising air causes cyclonic activity. The ionisation rate in the upper troposphere and the stratosphere is much higher during periods of quiet sun than during the sunspot maxima and may enhance the cyclonic activity. Increasing precipitation, run-off, and melting of ice, on the other hand, easily weaken the thermohaline circulation leading to a colder sea surface and a more continental climate, which, on the average, involves greater air pollution.