Ancient corals told the story of El Nino hundreds of years ago. Using this information, scientists were able to find out the water temperature in the ocean in the past – this will clarify the models of ocean heating. This is stated in a study by scientists from the University of Georgia, published in the journal Science.
El Nino is a climatic phenomenon that is characterized by a deviation of the surface temperature of the ocean in the equatorial part to a greater side from average values. This leads to climate change in various regions of the Earth, in particular, affects the amount of precipitation and weather.
In a new study, scientists analyzed the coral, about a thousand years old, which was discovered in the remote tropical Pacific Ocean. Corals, like rings of trees, store information about past events in the form of chemical indicators – oxygen isotopes.
The analysis showed that the ratio of oxygen isotopes sequestered in corals is an accurate measure of ocean temperatures for several hundred years and shows correlations between estimates of sulfate particles released into the atmosphere as a result of eruptions of tropical volcanoes and El Niño events.
“Many climate modeling studies show a dynamic relationship where volcanic eruptions can trigger El Nino events. We can use climate models for many centuries in the past, simulating volcanic eruptions over the past millennium – based on data obtained through analysis of ancient corals”.
Kim Cobb, lead author of the study