According to the conclusions of a new study by experts at the Weizmann Institute, it would appear that sulfur plays a much more important role in regulating the amounts of available atmospheric oxygen than researchers first established.
The investigations team was led by Itay Halevy, who is based at the WI Faculty of Chemistry's Environmental Science and Energy Research Department, University of Wisconsin expert Shanan Peters, and California Institute of Technology researcher Woodward Fischer.
Earth's sulfur cycle is extremely complex, experts say. As it moves from water to land, into the atmosphere, and then back again, the chemical undergoes a series of changes that can trigger shifts in the amounts of available carbon and oxygen.
Researchers have been aware of this connection for a long time, but it wasn't until the new study that they learned its exact influence and extent. Apparently, sulfur controls oxygen concentrations to a much higher degree than originally calculated.
The research team focused its efforts on understanding how the global carbon sulfur evolved over the past 550 million years. This is roughly the same interval when oxygen concentrations in the atmosphere rose to their current levels, of roughly 20 percent.
In order to do this, scientists used a database called Macrostrat, which contains data entries covering numerous rock samples collected from North American and elsewhere.
“This is the first use of Macrostrat to quantify chemical fluxes in the Earth system. I met my coauthors at a lecture I gave at Caltech, and we immediately began discussing how we might apply Macrostrat to understanding biogeochemical cycling,” says Peters, who manages the database.
“I think this study will open the door to many more uses of Macrostrat for constraining biogeochemical cycles,” he goes on to say, quoted by Astrobiology Magazine
“These findings, in addition to shedding new light on the role of sulfur in regulating oxygen levels in the atmosphere, represent an important step forward in developing a quantitative, mechanistic understanding of the processes governing the global sulfur cycle,” Halevy concludes.
Understanding Earth's natural cycles in detail is important because it can shed light on how global warming and climate change can influence the atmosphere, land and oceans. Computer models based on the new data could provide even more accurate predictions than currently possible.