Tropical corals add a new growth band each year (above). Corals the size of the one in the picture below are old enough to have acquired nearly 100 of these annual growth bands. The chemical makeup of each band reveals the temperature and saltiness of the water during the year in which it was formed. Scientists depend upon these and other glimpses into the past to infer how El Niño might behave in future climate scenarios. (Images courtesy of Robert B. Dunbar, Rice University.)
To download a postscript file of the coral for printing, click here.
To download a postscript file of the close-up view of coral for printing, click here.