Asian monsoon weather and climate and lake system changes on the Yunnan Plateau during the Late Holocene inferred from sclerochronological isotope patterns of gastropod shells and sediments from Xingyun and Fuxian lakes (Yunnan, China).

位于中国西南部的云南高原是研究亚洲季风与ENSO相互作用的重要地区。它代表了青藏高原的东南延伸，自全新世早期以来一直是暴露于极端气候的文化景观。到目前为止，严重的干旱，如2010-2011年期间发生的灾难性洪水，是不可预测的，因此表明了解极端气候变化的特征和潜在机制的重要性。我们认为，建立一个新的亚月分辨率的古天气档案可能有助于推断季风季节的开始，降水量和雨季的长度，或季风失败，以重建可能的周期在过去的ca。6 ka;基于此，我们可能能够预测未来极端气候的概率。我们已经确定了湖泊腹足类Margarya，这是非常丰富的晚第四纪沉积物中的星云湖，存档水文气象信号，可以sclerochronologically探索稳定同位素分析，每周分辨率超过至少三年的个体发育。在星云湖的初步调查表明，珍珠贝壳可以在百年分辨率的湖泊沉积物取芯检索，平均。这意味着，在过去6 ka的每一个世纪，气候信号都是由古气候变化引起的。3年的气候资料可用于分析气候极端事件和推断全新世中晚期的季节变化。通过与其他替代指标的比较和相关性，可以概述极端气候对文化发展的影响。

The Yunnan Plateau, in south-western China, is considered a key region for studying the interactions of the Asian monsoons with ENSO. It represents the south-eastern extension of the Tibetan Plateau and has been a cultural landscape exposed to climate extremes since the early Holocene. Severe droughts, such as during 2010-2011 which was followed by catastrophic floods, are unpredictable so far and thus demonstrate the importance of understanding characteristics and underlying mechanisms of climate extremes´ variability. We believe that establishing a new palaeo-weather archive of sub-monthly resolution may help to infer monsoon season onset, precipitation amount and length of the rainy season, or monsoon failure, in order to reconstruct possible cyclicities during the last ca. 6 ka; and based upon this we may be able to predict probabilities of future climate extremes. We have identified the shells of the lacustrine gastropod Margarya, which is extremely abundant in late Quaternary sediments of Xingyun Lake, to archive hydro-meteorological signals, that can be sclerochronologically explored by stable isotope analyses, in weekly resolution over ontogenies of at least three years. Preliminary investigations at Xingyun Lake have shown that Margarya shells can be retrieved by lake sediment coring in centennial resolution, in average. This means that for every century of the last 6 ka palaeo-weather signals of ca. 3 years are archived which can be used to analyze climate extremes and to infer Mid and Late Holocene seasonality changes. In comparison and correlation with other proxies the impact of climate extremes on the cultural development can be outlined.