Researchers from the U.S., Japan, and Canada used the Canadian Light Source (CLS) at the University of Saskatchewan to develop a method for determining past ocean temperatures from cultured corals in the laboratory. The team published their findings in Earth and Planetary Science Letters.
The scientists want to learn about our oceans’ past in order to better protect us from climate change.
“The significance of this study is we now have a new tool to study past seawater temperature,” said Prof. Xiao-Ming Liu with the Department of Earth, Marine and Environmental Sciences at the University of North Carolina at Chapel Hill. “If we know how seawater temperature changed in our past, it can inform our decisions for future climate warming.”
“We don't have a good record of what seawater temperature was millions of years ago,” she said. Or, not yet at least.
The team’s synchrotron-based study concluded that the composition of potassium isotopes in cultured coral is dependent on seawater temperature. These isotopes act as a geochemical tracer and will allow scientists to extrapolate the history of our oceans with natural coral samples.
Learning about the history of our oceans, including significant climate change events that happened long ago, will help researchers to better predict what might happen in our future, according to Dr. Liu.
“We use corals like a thermometer of the past ocean,” she said. “By studying history, we might avoid repeating the same mistakes.”
Li, Wenshuai, Xiao-Ming Liu, Kun Wang, Yongfeng Hu, Atsushi Suzuki, and Toshihiro Yoshimura. "Potassium incorporation and isotope fractionation in cultured scleractinian corals." Earth and Planetary Science Letters 581 (2022): 117393.DOI: 10.1016/j.epsl.2022.117393.
Canadian Light Source