New research, led by the University of Massachusetts Amherst, refines our understanding of the chemical traces that act as the rain’s fingerprint.
New research, led by the University of Massachusetts Amherst, refines our understanding of the chemical traces that act as the rain’s fingerprint. The work, which appeared recently in Global Biogeochemical Cycles, is crucial for understanding the Earth’s water cycle, especially as it undergoes rapid change due to global warming, deforestation and other environmental catastrophes.
You no doubt know that water, H2O, is composed of two molecules of hydrogen and one of oxygen. What you may not know is that there are a few different varieties of both hydrogen and oxygen. The “normal” hydrogen, for example, has a nucleus with only one proton, but there’s another version: “heavy hydrogen,” or deuterium, which has both a proton and a neutron in its nucleus. This deuterium is comparatively rarer, and it can be used both to track rainfall amounts over time as well as to understand evaporation and seasonal changes in climate. The same is true for oxygen, which has both a common light version and a rare heavy version.
“Deuterium excess,” or when the ratio of heavy hydrogen to heavy oxygen increases, is a fingerprint that is widely used in climate and hydrological modeling and for reconstructing past climates to understand the history of a raindrop. But the processes that lead to the excess of deuterium aren’t entirely understood. “Our paper is the first to look at seasonal variations of deuterium excess in rainfall across the globe to better understand what affects these chemical tracers at regional scales,” says Matthew Winnick, professor of geosciences at UMass Amherst, and the paper’s senior author.
Read more at University of Massachusetts Amherst
Photo Credit: Didgeman via Pixabay
