SHCal20

SHCal20 is a calibration curve used in radiocarbon dating to convert radiocarbon ages into calendar years. Developed by researchers from the University of Waikato and other institutions, SHCal20 provides a revised and updated calibration dataset that improves the accuracy of age estimations for samples dating from the last 50,000 years. It is based on a comprehensive compilation of calendar data derived from various sources, including speleothems, tree rings, and marine sediments, correlated with radiocarbon measurements.

The "SH" in SHCal20 indicates its primary focus on the Southern Hemisphere. This spatial distinction is important because the global radiocarbon reservoir effect can vary between hemispheres, influencing the calibration process. SHCal20 updates previous calibration curves, such as SHCal13, incorporating new data and improved statistical methods to refine age estimates.

Published in 2020, SHCal20 extends the calibration range from approximately 0 to 55,000 calibrated years before present (cal BP). It is widely used in archaeological, paleoenvironmental, and geochronological research to provide more precise calendar ages for radiocarbon-dated samples in the Southern Hemisphere.

The development of SHCal20 was part of ongoing efforts to improve calibration accuracy, accounting for fluctuations in atmospheric radiocarbon over time. It is publicly available and integrated into common calibration software and tools used by scientists worldwide, ensuring consistent and reliable age determinations across various disciplines.