quality:correction, structural:expansion, structural:scholar_edition
A paleothermometer is a methodology that provides an estimate of the ambient temperature at the time of formation of a natural material. Most paleothermometers are based on empirically-calibrated proxy relationships, such as the tree ring or TEX86 methods. Isotope methods, such as the δⁱ⁸O method or the clumped-isotope method, are able to provide, at least in theory, direct measurements of temperature.