Read the history of the storm through the tree

Oxygen extracted from the age ring on the trunk will help answer whether the storms are getting stronger and appear more often, US researchers said.

Dana Miller and colleagues at Knoxville University in Tennessee said they used the method to recreate the 220-year history of typhoon activity in southern Georgia.

These shallow root plants such as pine suck water from the surface, and this water source changes depending on rainfall. During storms, the oxygen content in the water is slightly different in structure.

Tropical storms produce large amounts of agglutination particles with much lower oxygen isotope components (about 10%) than typical equatorial storms.

These isotopes are absorbed by plants and accumulated in cellulose vessels. They stay there until the tree is cut down. Researchers can easily find the oxygen isotopes of different years by counting the number of tree rings. For example, they found evidence of three major storms in the 1870s.

Their findings have strengthened data about storms in recent times and showed that it was a good way to recount past history of storms.

Image reproducing the storm in 1872 (Photo: bergoiata.org)

T. An