Little is known about centennial- to millennial-scale climate variability during interglacial times, other than the Holocene. We here present high-resolution evidence from anoxic (unbioturbated) sediments in the eastern Mediterranean Sea that demonstrates a sustained ～800-yr climate disturbance in the monsoonal latitudes during the Eemian interglacial maximum (～125 ka BP). Results imply that before and after this event, the Intertropical Convergence Zone (ITCZ) penetrated sufficiently beyond the central Saharan watershed (～21°N) during the summer monsoon to fuel flooding into the Mediterranean along the wider North African margin, through fossil river/wadi systems that to date have been considered only within a Holocene context. Relaxation in the ITCZ penetration during the intra-Eemain event curtailed this flux, but flow from the Nile - with its vast catchment area - was not affected. Previous work suggests a concomitant Eurasian cooling event, with intensified impact of the higher-latitude climate on the Mediterranean basin. The combined signals are very similar to those described for the Holocene cooling event around 8 ka BP. The apparent type of concurrent changes in the monsoon and higher-latitude climate may reflect a fundamental mechanism for variability in the transfer of energy (latent heat) between the tropics and higher latitudes.
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机译：除全新世外，人们对冰川期间百年至千年尺度的气候变化知之甚少。我们在这里提供了来自东地中海缺氧（未生物扰动）沉积物的高分辨率证据，表明在Eemian冰期最大值（〜125 ka BP）期间，季风纬度持续〜800年的气候扰动。结果表明，在此事件之前和之后，热带辐合带（ITCZ）在夏季风期间已充分渗透到撒哈拉中部分水岭（〜21°N）以外，从而通过化石河/迄今为止，仅在全新世背景下才考虑了旱谷系统。在Eimain内事件期间ITCZ渗透率的放松限制了这种通量，但来自尼罗河的流域（其广阔的集水区）并未受到影响。先前的工作表明伴随有欧亚降温事件，高纬度气候对地中海盆地的影响加剧。组合的信号与针对8 ka BP附近的全新世冷却事件描述的信号非常相似。季风和高纬度气候并发变化的明显类型可能反映了热带和高纬度之间能量（潜热）传递变化的基本机制。
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