ClimCellMed - Climate dynamics during the late Holocene derived from Cell structure measurements of juniper trees in the eastern Mediterranean

当今非洲的很大一部分地区受到全球和环境变化的严重影响，直接导致或恶化了已经存在的社会问题。由于非洲大陆过去也经历了类似的变化，因此更详细地了解区域过去的气候动态是很重要的，因为已经假设环境变化在调节人类扩张、收缩甚至可能灭绝方面发挥了重要作用。在更全面地研究人类社会内部的变化和非洲的纠缠机制时，更可靠的区域气候重建将是有价值的背景资料。在世界许多地区，已经成功地完成了基于树轮的气候重建。由于年轮边界不清、重复、缺失或楔形，非洲的树状年代学往往很困难。在某些情况下，树木年轮被用作精确测年的高分辨率气候指标。来自赤道以北非洲树木的长期重建非常罕见，我们认为这是古气候数据库中的一个关键缺口。在赤道以北的非洲，由于森林面积非常有限，未来的树木年轮记录前景普遍黯淡。来自非洲树木的树枝考古可测得年代的木材非常罕见，但从土耳其进口的木材(雪松、刺柏和柏木)的树木考古可测得的木材很常见。出于树状气候学的目的，从土耳其S南部海岸腹地的金牛座山脉进口的刺柏被视为北非最有前途的物种。该项目的主要目标是将来自活的树木和考古遗址的木质刺柏材料结合在一起，并首次在地中海建立一个追溯到公元前3000年的长期重建，利用最近开发的一种方法，应用共聚焦激光扫描显微镜测量树木年轮的细胞结构。由此得到的单元格结构年表将被细分为几个类别，每个树轮只包含一小部分单元格行。由此产生的亚年表代表了亚季节性细胞生长模式。这些分年表将与季节性气候数据相关联，并将得出额外的季节性气候信息。随后的分析将审查与地中海东部和非洲东北部气候变化的大气和海洋模式(例如，ENSO、NAO和季风)的关系，调查过去火山喷发的影响，并确定对该区域人类社会可能产生的气候影响。

Large parts of present-day Africa are affected severely by global and environmental change, resulting directly in or worsening already existing societal problems. Since the continent has gone through similar changes in the past, it is important to comprehend the regional past climate dynamics in more detail, since it has been hypothesised that environmental change played a significant role in conditioning human expansions, contractions and possibly even extinctions. More reliable regional climate reconstructions will be valuable background information when studying the transformations within human societies and entanglement mechanisms in Africa more comprehensively. In many parts of the world tree-ring based climate reconstructions have been accomplished successfully. African dendrochronology is often difficult because of indistinct, double, missing or wedging ring boundaries. In some instances, tree rings have been used as precisely dated high-resolution climate proxies. Long-term reconstructions derived from trees growing in Africa north of the equator are very rare, which we believe is a crucial gap in the palaeoclimate database. The future prospects for long tree-ring records in Africa north of the equator are generally bleak due to the very limited forested area. Dendroarchaeologically datable wood from African trees is very rare but dendroarchaeologically datable wood from timber (cedar, juniper and cypress) imported from Turkey is common. For dendroclimatological purposes, juniper imported from the Taurus Mountains in the hinterland of Turkey´s southern coast is seen as the most promising species in northern Africa. The main goal of the project is to combine woody juniper material from both living trees and archaeological sites, and to establish, for the first time, a long reconstruction in the Mediterranean back to 3000 BC, utilizing a recently developed method applying confocal laser scanning microscopy for measuring cell structures of tree rings. The resulting cell structure chronologies will be subdivided into several classes, containing only a fraction of cell rows per tree-ring. The resulting sub-chronologies represent sub-seasonal cell growth patterns. Such sub-chronologies will be correlated with seasonal climate data and additional seasonal climate information will be derived. Subsequent analyses will examine relationships to the atmospheric and oceanic modes of climate variability (e.g., ENSO, NAO and Monsoon) in the eastern Mediterranean and northeast Africa, investigate the impact of past volcanic eruptions and identify possible climate effects on human societies in the region.