Abstract Understanding the regional hydroclimatic variability beyond the instrumental period is essential to contextualize the current climatic period within a longer record. Dendrochronology has been used as a powerful tool for estimating the temperature and precipitation variability of the last centuries on an annual and even seasonal scale. However, most of the centenary trees in Spain are located in high-elevation mountain environments, so the reconstructed signal is not representative of the climate variability of the lowlands, where the main cities and most of the population and human activities are located. Here we present a precipitation reconstruction of the Bardenas Natural Park, a semi-arid environment within the Ebro Valley, based on 61 new tree-ring width series of Pinus halepensis Mill. The new chronology, calibrated against high-resolution instrumental precipitation data, uncovers a high and robust relationship with the annual precipitation (from previous June to current May) (1951−2012 CE; r = 0.78;), representing the precipitation totals of the hydrological year. Our reconstruction explains 61 % of the annual precipitation for the period 1951−2012 and is representative of the lowlands of the Northeast of Spain. We identified 12 extremely dry and 11 extremely wet years, finding the first half of the 20th century to be the period with most extreme episodes of the reconstruction. Additionally, we found a strong agreement between our tree-ring based reconstruction and the lowlands documentary-based drought estimators (rogation ceremonies). These findings contribute to improving our understanding of past hydroclimatic variability in semi-arid lowland areas where available proxy records are rare.

中文翻译：

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沙漠中的雨；从西班牙巴德纳斯自然公园的阿勒颇松推断过去 156 年的降水重建

摘要 了解仪器时期以外的区域水文气候变化对于将当前气候时期置于更长的记录中至关重要。树木年代学已被用作在年度甚至季节性尺度上估计过去几个世纪的温度和降水变化的有力工具。然而，西班牙的百年树大多位于高海拔山区环境，因此重建的信号不能代表低地的气候变化，主要城市和大部分人口和人类活动所在的低地。在这里，我们展示了巴德纳斯自然公园的降水重建，巴德纳斯自然公园是埃布罗谷内的一个半干旱环境，基于 61 个新的树轮宽度系列的松树。新的年表，根据高分辨率仪器降水数据进行校准，揭示了与年降水量（从前 6 月到今年 5 月）（1951-2012 CE；r = 0.78；）之间的高度和稳健的关系，代表了水文年的降水总量。我们的重建解释了 1951-2012 年年降水量的 61%，代表了西班牙东北部的低地。我们确定了 12 个极度干旱和 11 个极度潮湿的年份，发现 20 世纪上半叶是重建过程中最极端的时期。此外，我们发现基于树木年轮的重建与基于低地纪录片的干旱估算器（rogation ceremonies）之间存在很强的一致性。