Who uses radiometric dating
Also, the Sun’s own magnetic field varies with the cycle, and that could change the way cosmic particles bombarded the Earth.
In 1961, Minze Stuiver suggested that longer-term solar variations might account for the inconsistent carbon-14 dates. Libby, for one, cast doubt on the idea, so subversive of the many dates his team had supposedly established with high accuracy.(9) Suess and Stuiver finally pinned down the answer in 1965 by analyzing hundreds of wood samples dated from tree rings.
It was an anxious time for scientists whose reputation for accurate work was on the line.
But what looks like unwelcome noise to one specialist may contain information for another.
Thus the less of it that remained in an object, in proportion to normal carbon, the older the object was.
De Vries thought the variation might be explained by something connected with climate, such as episodes of turnover of ocean waters.(7) Another possible explanation was that, contrary to what everyone assumed, carbon-14 was not created in the atmosphere at a uniform rate.
Some speculated that such irregularities might be caused by variations in the Earth's magnetic field.
In 1958, Hessel de Vries in the Netherlands showed there were systematic anomalies in the carbon-14 dates of tree rings.
His explanation was that the concentration of carbon-14 in the atmosphere had varied over time (by up to one percent).