SHCal13

SHCal13 is the Southern Hemisphere radiocarbon calibration curve published in 2013 for converting radiocarbon ages into calendar ages for samples from the Southern Hemisphere. It provides the relationship between atmospheric 14C content and calendar year, reflecting hemispheric differences in carbon exchange and reservoir effects.

Developed by an international team under the Southern Hemisphere Calibration (SHCal) project, SHCal13 updates the calibration framework available for Southern Hemisphere samples and complements the Northern Hemisphere IntCal13 curve. The curve integrates atmospherically derived 14C records from Southern Hemisphere tree rings and other archives with marine and terrestrial data to produce a continuous calibration reference up to roughly 50,000 calendar years before present.

Data sources include dendrochronological records from southern continents and marine records such as corals, which are combined with statistical treatments to characterize uncertainties. SHCal13 is used to calibrate conventional radiocarbon ages obtained from terrestrial and marine material, enabling researchers to assign calendar-age ranges for archaeological, paleoclimate, and geological records. For marine specimens, the curve incorporates reservoir corrections to account for regional offsets in marine radiocarbon ages in the Southern Hemisphere.

Impact and usage of SHCal13 are widespread in radiocarbon dating of Southern Hemisphere material, and it is typically employed with calibration software to produce calendar-age estimates with stated confidence intervals. As part of ongoing verification and improvement, SHCal13 has since been superseded by SHCal20 (introduced around 2020), which updates data and methods for greater accuracy.