Two tree-ring series, one from a high-latitude pine tree (located in northern Scandinavia) and one from a mid-latitude oak tree (located in eastern Germany) were analyzed for radiocarbon (14C) at annual resolution. The new records cover the calendar date ranges 290–460 AD and 382–486 AD, respectively, overlapping by 79 yr. The series show similar trends as IntCal13. However, some significant deviations around 400 AD are present with lower Δ14C (higher 14C ages). An average offset between the two new series and IntCal13 of about 20 years in conventional 14C age is observed. A latitudinal 14C offset between the tree sites in central and northern Europe, as would be expected due to the relatively large spatial distance, is not recorded, however. Periodic changes in the 14C records are resolved that can be attributed to the “11-year” solar cycle (Schwabe cycle) with cycle length from 9 to 11 years. The magnitude of changes in Δ14C due to the solar cycle is between 1.5 and 3‰. Since solar cyclicity is only partially synchronous between the two new series, reasons for asynchronicity are explored.

中文翻译：

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公元 400 年左右的年度 14C 树轮数据：中高纬度记录

对两个树轮系列，一个来自高纬度松树（位于斯堪的纳维亚北部）和一个来自中纬度橡树（位于德国东部）进行了放射性碳分析（14C) 年度决议。新记录分别涵盖了公元 290-460 年和公元 382-486 年的日历日期范围，重叠了 79 年。该系列显示出与 IntCal13 类似的趋势。然而，在 400 AD 左右存在一些显着偏差，Δ 较低14C（更高14C 年龄）。两个新系列与 IntCal13 之间的平均偏移量约为 20 年传统14观察到 C 年龄。一个纬度14然而，由于空间距离相对较大，中欧和北欧的树点之间的 C 偏移量没有记录。周期性变化14C 记录可归因于“11 年”太阳周期（施瓦贝周期），周期长度为 9 至 11 年。Δ的变化幅度14由于太阳周期，C在1.5和3‰之间。由于太阳周期在两个新系列之间仅部分同步，因此探索了不同步的原因。