SGER: Tropical Tidal Flat Archive of Global Climate Variations

这是SGER(探索性研究小额赠款)奖。西大西洋的热带潮滩沉积可能包含了过去几千年来气候变化的独特带状记录。这些平台的局部粘性表面就像飞纸一样，保留着来自非洲的气溶胶，厘米厚的海洋沉积物层记录着飓风的经过。飓风的频率和来自非洲的气溶胶流量都反映了全球范围内气候的变化。为了探索这种气候变化的潜在记录，将收集一系列岩心，以获取过去3000年或更长时间持续积累的沉积物。记录主要风暴的沉淀层将被记录下来，其组成将被确定；气溶胶将从风暴间藻层中提取，称重，并通过X射线衍射和光学显微镜确定其组成。为了确定风暴层的年代和确定气溶胶的累积速度，岩芯的部分将用放射性碳测年，可能还会用理论230测年。这一试点项目可能会产生飓风频率和气溶胶通量的当地记录，通过将该方法应用于其他潮滩沉积，有可能开发更大面积的记录。这项探索性研究很重要，因为如果成功，它将提供不同全球气候制度下风暴频率的信息。

This is an SGER (Small Grants for Exploratory Research) award. Tropical tidal flat deposits of the Western Atlantic may contain a unique strip-chart-like record of variations in climate during the past few thousand years. The locally-adhesive surfaces of these flats act like fly-paper to retain aerosols from Africa and centimeter-thick layers of marine sediment record the passage of hurricanes. Both the frequency of hurricanes and the flux of aerosols from Africa reflect global-scale variations in climate. To explore this potential record of climate variations, a series of cores will be collected for sediments that have accumulated continuously for the past 3000 years or more. The sediment layers that record major storms will be logged and their compositions determined; the aerosols will be extracted from the inter-storm algal layers, weighed and their compositions determined by x-ray diffraction and optical microscopy. To date the storm layers and determine rates of accumulation of aerosols, sections of the cores will be dated by radiocarbon and possibly with thorium230. This pilot project may produce a local record of hurricane frequency and the flux of aerosols and by applying the method to other tidal flat deposits, it is possible to develop the record of a much larger area. This exploratory research is important because, if successful, it will provide information of storm frequency under different global climate regimes.