Sclerochronology

The field of coral sclerochronology arose from initial observations of external growth ridges, variations of internal skeletal structures, and apparent relationships between environmental conditions and coral growth. The confirmation of the annual nature of density banding led to modern methods of X-radiography, densitometry, and measurement of growth parameters: extension, density, and calcification. Coral sclerochronology has demonstrated its utility by advancing our understanding of coral growth ecology along with anthropogenic impacts and environmental influences on growth rates. The skeletal basis of density banding revealed on X-radiographs is well described; however, the fundamental cause of density banding has yet to be clearly defined. Based on decades of published research on coral growth rates and environmental influences, it is clear that coral growth is not a fully controlled by a single environmental limiting factor, in contrast to the analogous field of dendrochronology. The value of coral sclerochronology lies in the ability of corals to store records of growth in their skeleton, over long periods of time, which reflect the sum total of environmental and climatic controls. The field of coral sclerochronology is continually advancing and provides unique records, throughout the tropical and sub-tropical oceans, of potential climatic/environmental change and anthropogenic influence.