Which isotopes are the most abundant in water?
The number of isotopes in the atmosphere has tripled since the Industrial Revolution, but the amount of oxygen and sulfur compounds we have in our water supply is declining rapidly, a new study finds.
The findings come from a survey of the isotopic composition of the Earth’s water.
“Our research shows that atmospheric water is more reactive to atmospheric oxygen than any other gas on Earth,” said lead researcher Shashank Jha, a postdoctoral researcher at the University of California, Berkeley.
“That means the atmosphere is more likely to produce reactive compounds like sulfur dioxide, which has been associated with climate change.”
The team compared the isotope composition of different types of water with their chemical fingerprints, looking for the most common compounds, and then used simulations to see how the chemical signatures differed between the different water molecules.
The team found that most of the atmospheric water, which consists of hydrogen, oxygen, carbon, nitrogen, and methane, is reactive.
It’s this hydrogen and oxygen that are found in the ocean, which accounts for about 70 percent of the water’s total volume.
The rest is a mixture of organic matter, water, and carbon compounds.
The most abundant atmospheric nitrogen, in the form of carbonates, is found in trace amounts in the water, but there is less of it in the oceans than in the soil.
The researchers found that the methane, or short-chain fatty acids, that are present in the surface water have about a third of the nitrogen and hydrogen content of the atmosphere.
“This suggests that atmospheric nitrogen concentrations have been increasing for some time, and the atmospheric methane concentrations are rising,” Jha said.
In the study, published today in the journal Nature, the researchers used computer simulations to calculate the isotopes that make up atmospheric water.
By combining those simulations with a detailed understanding of the composition of all the water molecules in the world, the scientists were able to calculate that the atmosphere contains about 3,500 atoms of nitrogen, 7,400 atoms of hydrogen and 3,400 of carbon.
The carbon-containing isotopes, known as the tropospheric water molecules, are the only ones that have a significant effect on the composition and chemical fingerprinting of the air.
The isotopes make up the bulk of the oxygen in the air, which is what makes it reactive.
They’re also responsible for some of the sulfur compounds in the land and water, because they’re the building blocks of the ozone layer.
Because the atmosphere doesn’t contain all the atmospheric oxygen, the oxygen and methane are the major sources of reactive oxygen and carbon, the study found.
The remaining atmospheric water molecules are more reactive, which means they’re making up less than 1 percent of total atmospheric water and sulfur.
They also make up less nitrogen than the troposphere water, a finding that could mean the oceans are getting more reactive.
This would have implications for how much carbon dioxide and other greenhouse gases are released from the atmosphere, the authors wrote.
The troposphere, on the other hand, is a relatively inert atmosphere with only trace amounts of nitrogen and methane.
The authors believe that because the tropics are less reactive, they’re getting less carbon dioxide.
But the tropic water molecules do contribute to atmospheric carbon dioxide, Jha added.
“The tropics have a high carbonate content, so that’s a bit of an issue.
The problem is that the tropical water molecules can react to carbon dioxide more quickly, so we have to look at the tropically higher carbonate concentrations,” he said.
The results suggest that we should be looking at oceanic carbonate, the type of carbon found in oceans, Jhas said.
That would mean that the ocean is getting more carbon dioxide than it used to, which would mean more carbon emissions.
“It’s going to have a huge impact on our climate,” Jhhas said.
“We’re getting more and more carbon from the oceans.”
The researchers also found that in the tropocities, the sulfur isotopes of carbonate and sulfate make up about 60 percent of all of the methane.
That’s not a huge amount of sulfur in the environment, but it does indicate that the water is getting reactive.
That makes sense given that methane is produced by burning fossil fuels.
“Methane is a major contributor to the carbon cycle, and a significant contributor to climate change,” Jho said.
So if we have a big increase in methane, the carbon dioxide emitted would be offset by the reduction in methane.
This is a very important result because if we’re going to reduce our carbon emissions, we need to reduce methane production, he added.
The paper’s co-authors include Jha’s professor of chemistry and biogeochemistry, Matthew S. Pappas; Pappass’ graduate student, Emily J. Miller; and graduate student Yulia D. Sazonova.
The work was supported by the National Science Foundation and the Howard Hughes Medical