According to the NASA article provided to our class, it seems that the only well-defined and understood effects of aerosols involve global cooling and not global warming, whether from directly reflecting the sun or from increasing cloud coverage and therefore indirectly reflecting of the sun. However, there are several factors which complicate the effects of aerosols, making this simple prescription of effects far from accurate. For example, aerosols have the potential to decrease rainfall, and many aerosols trap reemitted heat as well as they reflect entering sunlight, adding to the greenhouse effect and contributing to heating as much as to cooling.
Another major twist in the plot, so to speak, involves the nature of specific aerosols. Though overall, the presence of these aerosols may block solar radiation from entering the atmosphere, this measurement does not account for the difference between man-made and natural aerosols or the chemical makeup and specific effects of different aerosols. As such, the climate effects created specifically by human aerosols, and therefore the ones which are variable and likely increasing, have not been well-studied in isolation. Dust in the air may create longer-lasting clouds, but there has always been dust in the air, and as such it is not particularly relevant to the discussion of climate change. What is relevant, however, are the aerosols created by industrial plants or increased by human behaviors like sulfates and black carbon.
It's still not fully clear how aerosols will affect climate. Based on the articles provided, I predict that the net effect will likely be global cooling, potentially a positive in the wake of other factors leading to global warming. However, because there is the possibility of decreased rainfall as well as damage to human health from harsher chemical aerosols, the situation is not all positive, and even global cooling caused by aerosols could have unforseen effects.
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