Proxy

A proxy climate indicator is a record that is interpreted, using physical and biophysical principles, to represent some combination of climaterelated variations back in time. Climate-related data derived in this way are referred to as proxy data. Examples of proxies include pollen analysis, tree ring records, speleothems, characteristics of corals, and various data derived from marine sediments and ice cores. Proxy data can be calibrated to provide quantitative climate information.