The term sulfate aerosols is used for a suspension of fine solid particles of a sulfate

Sulfate

In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...

 or tiny droplets of a solution of a sulfate or of sulfuric acid

Sulfuric acid

Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...

 (which is not technically a sulfate). They are produced by chemical reactions in the atmosphere

Atmosphere

An atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...

 from gaseous precursors (with the exception of sea salt

Sea salt

Sea salt, salt obtained by the evaporation of seawater, is used in cooking and cosmetics. It is historically called bay salt or solar salt...

 sulfate

Sulfate

In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...

 and gypsum

Gypsum

Gypsum is a very soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is found in alabaster, a decorative stone used in Ancient Egypt. It is the second softest mineral on the Mohs Hardness Scale...

 dust particles

Mineral dust

Mineral dust is a term used to indicate atmospheric aerosols originated from the suspension of minerals constituting the soil, being composed of various oxides and carbonates. Human activities lead to 30% of the dust load in the atmosphere...

). The two main sulfuric acid precursors are sulfur dioxide

Sulfur dioxide

Sulfur dioxide is the chemical compound with the formula . It is released by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide unless the sulfur compounds are removed before burning the fuel...

 (SO₂) from anthropogenic

Anthropogenic

Human impact on the environment or anthropogenic impact on the environment includes impacts on biophysical environments, biodiversity and other resources. The term anthropogenic designates an effect or object resulting from human activity. The term was first used in the technical sense by Russian...

 sources and volcano

Volcano

2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

es, and dimethyl sulfide

Dimethyl sulfide

Dimethyl sulfide or methylthiomethane is an organosulfur compound with the formula 2S. Dimethyl sulfide is a water-insoluble flammable liquid that boils at and has a characteristic disagreeable odor. It is a component of the smell produced from cooking of certain vegetables, notably maize,...

 (DMS) from biogenic

Biogenic substance

A biogenic substance is a substance produced by life processes. It may be either constituents, or secretions, of plants or animals. A more specific name for these substances is biomolecules.-Examples:...

 sources, especially marine plankton

Plankton

Plankton are any drifting organisms that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. That is, plankton are defined by their ecological niche rather than phylogenetic or taxonomic classification...

. 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 gas

Greenhouse gas

A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in the Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone...

es, and therefore their cooling is localized and temporary. Other side effects of sulfate aerosols in the environment include poor air quality.

See also

• CLAW hypothesis
  CLAW hypothesis
  The CLAW hypothesis proposes a feedback loop that operates between ocean ecosystems and the Earth's climate. The hypothesis specifically proposes that particular phytoplankton that produce dimethyl sulfide are responsive to variations in climate forcing, and that these responses lead to a negative...
  
  
• Cloud condensation nuclei
  Cloud condensation nuclei
  Cloud condensation nuclei or CCNs are small particles typically 0.2 µm, or 1/100 th the size of a cloud droplet ) about which cloud droplets coalesce. Water requires a non-gaseous surface to make the transition from a vapour to a liquid. In the atmosphere, this surface presents itself as tiny...
  
  
• Sulfur cycle
  Sulfur cycle
  The sulfur cycle are the collection of processes by which sulfur moves to and from minerals and living systems. Such biogeochemical cycles are important in geology because they affect many minerals...
  
  
• Stratospheric sulfur aerosols
  Stratospheric sulfur aerosols
  Stratospheric sulfur aerosols are sulfur-rich particles which exist in the stratosphere region of the Earth's atmosphere. The layer of the atmosphere in which they exist is known as the Junge layer, or simply the stratospheric aerosol layer. These particles consist of a mixture of sulfuric acid...