Paleo Slide Set: Coral Paleoclimatology
Long Delta 18O record from Urvina Bay, Galapagos.

The last figure demonstrated the accuracy of coral d18O as a proxy measurement 
of sea surface temperatures. d18O can also serve as a proxy measurement for precipitation, 
particularly in areas like the central Pacific where large ENSO-related oscillations 
in annual rainfall occur. Now that scientists have established the reliability of coral 
d18O as a proxy signal, they are beginning to take deeper cores that provide increasingly 
long climatic records. Think of coral d18O as a paleothermometer that enables us to answer 
important questions about climatic variability in the world's oceans. This core from the 
Galapagos Islands gives us a 350-year record of sea surface temperatures and, by extension, 
El Nino activity in the eastern Pacific.

Photo Credits:
Thomas.G. Andrews
NOAA Paleoclimatology Program