Fossil Coral Cores (image) Georgia Institute of Technology Caption Fossil coral cores taken from the Line Islands provide information about the strength of the El Nino Southern Oscillation (ENSO) for periods of time as much as 7,000 years ago. The paper rules track the direction of coral growth. Credit Georgia Tech Photo: Gary Meek Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.