Oxygen isotope ratios from oak tree rings are used to extend the May–August precipitation totals of the England and Wales precipitation series back to 1201 ce. The agreement between instrumental and reconstructed values is unusually strong, with more than half of the variance explained and standard verification tests passed. The stability of this relationship is confirmed using split‐period calibration and verification. This allows the reconstruction to be variance‐scaled to the full length of the instrumental series back to 1766. Direct comparison with historical reports of very wet and dry summers show good agreement. Near‐constant replication, with a minimum of 10 timbers sourced from historic buildings across central southern England ensures signal strength does not change over time. Summers during the late 20th century appear anomalously dry and those of the 21st century very close to the pre‐20th century average with no evidence in the record of prolonged ‘megadroughts’ across England and Wales.

中文翻译：

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英格兰和威尔士地区的夏季降水（1201-2000 ce）来自橡树环中的稳定氧同位素

橡树环上的氧同位素比率用于将英格兰和威尔士降水系列的5月至8月的降水总量扩展到1201 ce。仪器值和重构值之间的一致性异常强，解释了一半以上的差异，并通过了标准验证测试。这种关系的稳定性可以通过分期校准和验证来确认。这使重建可以方差缩放到整个乐器系列的长度，可以追溯到1766年。与非常潮湿和干燥的夏季的历史报告进行的直接比较显示出很好的一致性。几乎恒定的复制，至少有10种木材来自英格兰中南部的历史建筑，以确保信号强度不会随时间变化。20世纪末的夏季异常干燥，而21世纪的夏季非常接近20世纪前的平均水平，在英格兰和威尔士的长期“特大干旱”记录中没有证据。