High-resolution Bronze Age palaeoenvironmental change in the Eastern Mediterranean: exploring the links between climate and societies

Bronze Age archaeological records from the eastern Mediterranean identify two periods of widespread so-called societal ‘collapse’ between ca. 4.50–ca. 4.20 cal ka BP and ca. 3.50–ca. 2.80 cal ka BP, respectively, which have been linked to a number of proposed causes, including climate change. However, the role of climate change in the ‘collapse’ of eastern Mediterranean Bronze Age societies has been questioned due to the resolution of climate proxy records. In this paper we present a regional synthesis of the highest resolution palaeoclimate records and compare these to archaeological evidence. By recalibrating radiocarbon dates onto a consistent timescale and using pollen, oxygen and carbon isotopes from both marine and terrestrial deposits, we reconstruct aridity at a 50-year resolution. Our results challenge a simple ‘climate destroyed society’ hypothesis. Instead, we find a more complex record of changing aridity and societal response and provide a nuanced perspective on climate versus non-climate causes of Bronze Age societal ‘collapse’ events. Our results have implications for the generation of palaeoclimate records aimed at exploring links between climate and societal change, emphasising the need for high resolution records proximal to archaeological sites.东地中海（eastern Mediterranean）地区的青铜时代（Bronze Age）考古记录显示，在约距今4.50~4.20校准千年距今年（calibrated thousand years before present，cal ka BP）和约距今3.50~2.80校准千年距今年（cal ka BP）两个时段，曾发生两次大范围的所谓社会“崩溃”事件，现有研究已将其与包括气候变化在内的多种潜在成因相关联。然而，由于气候代用记录（climate proxy records）的分辨率限制，气候变化在东地中海青铜时代社会崩溃中所扮演的角色一直受到学界质疑。本文针对最高分辨率的古气候记录（palaeoclimate records）开展区域综合研究，并将其与考古证据（archaeological evidence）进行对比分析。通过将放射性碳定年数据（radiocarbon dates）重新校准至统一时间标尺，并利用海相沉积物（marine deposits）与陆相沉积物（terrestrial deposits）中的孢粉（pollen）、氧同位素（oxygen isotopes）与碳同位素（carbon isotopes）数据，我们以50年的时间分辨率重建了区域干旱化演化过程。本研究结果对“气候摧毁社会”这一简单假说提出了质疑。与之相反，我们发现了干旱化变化与社会响应之间更为复杂的关联，并为青铜时代社会崩溃事件的气候与非气候成因提供了更为细致入微的解读视角。本研究结果对旨在探索气候与社会变化关联的古气候记录构建工作具有重要指导意义，同时强调了获取靠近考古遗址（archaeological sites）的高分辨率古气候记录的必要性。