SHCal04

SHCal04 is the Southern Hemisphere radiocarbon calibration curve used to translate radiocarbon ages into calendar ages for samples collected south of the equator. Published in 2004 as the southern counterpart to IntCal04, SHCal04 combines radiocarbon data from diverse southern archives to represent atmospheric 14C variations in the Southern Hemisphere and to align with the Northern Hemisphere record.

The curve draws on multiple proxy sources, including corals from southern tropical and temperate waters, lake- and peat-derived sediments with independent age controls, and dendrochronologically dated terrestrial materials where available. By integrating these data, SHCal04 provides a time-ordered relationship between radiocarbon years Before Present and calendar years, including corrections for regional reservoir effects where appropriate and for other known offsets in carbon cycling.

SHCal04 is used with calibration software such as CALIB or OxCal to convert 14C ages to calendar ages for samples originating in southern latitudes. It facilitates comparability with Northern Hemisphere records calibrated with IntCal04 and supports investigations of hemispheric differences in atmospheric 14C production and carbon cycle dynamics over the late Pleistocene and the Holocene.

Limitations of SHCal04 include uncertainties in older age ranges where proxy data are sparse and potentially variable reservoir effects among marine and terrestrial samples. As later data and methods became available, SHCal04 was superseded by subsequent curves (such as SHCal13 and later SHCal20), which incorporate new measurements and updated calibrations.