Hence the effects of aerosols will largely be concentrated near their sources, or downwind. The major sources of sulphate aerosols, for example, are in Europe, eastern North America, and eastern Asia. The southern hemisphere, by contrast, is quite clean. However, these patterns are expected to change, as pollution controls act to reduce emissions of sulphur dioxide in industrialised nations. On the other hand, developing nations currently place much lower importance on such issues.
Aerosols affect our environment at the local, regional, and global levels.
At the local level, aerosols are now becoming recognised as a significant health problem, especially in regard to respiratory illnesses, including asthma. These conclusions are still being debated, and better data on both the physical and chemical properties of aerosols, and illness patterns, are being actively sought. Aerosols may also have a significant impact on visibility, with potential economic consequences for tourism, for example. Climate Forcing Atmospheric aerosols influence climate in two main ways, referred to as direct forcing and indirect forcing. In the direct forcing mechanism, aerosols reflect sunlight back to space, thus cooling the planet.