Sulphate aerosols
The term sulfate aerosols is used for a suspension of fine solid particles of a sulfate or tiny droplets of a solution of a sulfate or of sulfuric acid (which is not technically a sulfate). They are produced by chemical reactions in the atmosphere from gaseous precursors (with the exception of sea salt sulfate and gypsum dust particles). The two main sulfuric acid precursors are sulfur dioxide (SO2) from anthropogenic sources and volcanoes, and dimethyl sulfide (DMS) from biogenic sources, especially marine plankton. These aerosols can cause a cooling effect on earth.
However the UNFCCC has noted that sulfate aerosols remain in the atmosphere for only a short amount of time in comparison to other greenhouse gases, and therefore their cooling is localized and temporary. Other side effects of sulfate aerosols in the environment include poor air quality.
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