Denniston awarded grant to examine ancient El Niño
Geology Professor and Environmental Studies director Rhawn Denniston has been awarded a $26,550 grant to conduct research on El Niño activity from millions of years ago.
The grant, titled “The El Niño-Southern Oscillation in a Warming World: Developing Coral Records of Ocean Variability from Past Greenhouse Periods,” was awarded by the Center for Global and Regional Environmental Research (CGRER).
The project will involve field work in Central America to collect fossil corals and lab work at the University of Wisconsin and Iowa State University to analyze the samples. Cornell students will be involved in the lab work.
Previous aspects of this project were funded through grants to Denniston from the Petroleum Research Fund and the National Science Foundation, the latter of which supported the honors thesis of geology major Thomas Weiss, a 2016 Cornell graduate now working toward a Ph.D. in paleoclimatology at Columbia University.
The aim of the study is to better understand El Niño, a part of the larger component of the climate system called the El Niño-Southern Oscillation (ENSO), one of the biggest reasons that climates change from year to year on a global scale. ENSO is closely tied to ocean temperature and impacts coral bleaching and fishing. It is also closely linked to rainfall, and thus food production, across many areas of the globe and has been linked to civil unrest going back hundreds of years (including the French Revolution).
“There is good evidence that the number and strength of El Niños, and their sister events called La Niñas, has changed over recent centuries and millennia, and climate models suggest they are likely to change in our warming world,” Denniston said. “One way to help understand future El Niño is by looking at past ‘greenhouse worlds’ when atmospheric carbon dioxide levels and temperatures were at or above modern values. Tom looked at this question by analyzing a rare, extremely well-preserved Miocene (five-million-year-old) coral from the Dominican Republic and found evidence of modern ENSO-like activity.”
The grant supports work to look at corals from a younger time called the Pliocene, which lasted from 5 to 2 million years ago. Extremely well preserved fossil corals such as are required for this work are found in a few spots in Central America. Kelsey Feser, a 2010 Cornell graduate now completing a two-year appointment as visiting assistant professor at Cornell, will join Denniston in the field later this year.