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What are aerosols?
Aerosols consist of small liquid or solid suspended particles that linger in the atmosphere for some time.
They are usually between a few nanometers and ten micrometers in size.
Aerosols can be of natural or anthropogenic origin, i.e. they can be man-made.
They arise from volcanic eruptions, desert storms or come as salts from the ocean.
Man-made sources include fossil fuels.
Aerosols can affect the climate in a variety of ways: On the one hand, they can scatter solar radiation, which has a cooling effect on the climate system.
But they can also absorb radiation, which is more likely to contribute to warming.
Studies come to the conclusion that the cooling effects of aerosols predominate.
How aerosols affect the microphysics of clouds also plays a role: They act as condensation nuclei, water attaches itself to the smallest particles and cloud droplets are formed.
A high aerosol concentration can create clouds that have many water droplets that reflect solar radiation more strongly.
How do aerosols affect climate change?
How strong the influence of anthropogenic aerosols in particular is on climate change has not been conclusively clarified.
However, scientists assume that in the course of industrialization, the emission of anthropogenic aerosols has also increased.
According to this, these aerosols had at least one mitigating effect on global warming in the past, i.e. air pollution had a cooling effect.
It is questionable whether this influence will continue.
Because at least in western countries it has already been possible to improve the air quality in favor of health protection and thus to reduce the proportion of anthropogenic aerosols.
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