Sulfur Cycle

Sulfur exists in oxidation states:

from -2 to +6

Elemental Sulfur

Yellow, crystalline solid at room temperature

Found in volcanic deposits and hot springs

Inorganic Sulfur Species

Sulfide (S^2-)

Sulfite (SO₃^2-)

Sulfate (SO₄^2-)

Climate Change and Sulfur

Sulfur Dioxide (SO₂) and Aerosols

Dimethyl Sulfide (DMS)

Sulfate Availability in Salt Marshes

Sulfur Dioxide (SO₂) and Aerosols

Cooling effect as SO₂ released into the atmosphere forms sulfate aerosols, which reflect sunlight back into space

• may come from volcanic eruptions or anthropogenic sources

Dimethyl Sulfide (DMS) and Climate Change

Marine phytoplankton produces DMS, which enters atmosphere and forms sulfate aerosols

• influence cloud formation and brightness

Sulfate Availability in Salt Marshes

sulfate reduction is energetically more favorable than methanogenesis, which causes sulfate reduction to dominate anaerobic decomposition and suppress methane production

• influenced by the high levels of sulfate in seawater