NOAA/WDS Paleoclimatology - Defore Cave Geochemical Data from 730 to -46 Cal Yr BP

Meteorological records of monsoon rainfall in the Indian Ocean are generally less than 100 years long. The relative brevity of these records makes it difficult to investigate monsoon variation on decadal and centennial timescales, to determine what factors influence the intensity of rainfall on these timescales, or to place possible changes in the twentieth century into a broader historical context. Development of a geologic proxy for rainfall that records annual variation in the monsoon over much longer time periods than are covered by instrumental records would be a significant step forward. We have developed an annually resolved record of monsoon rainfall variation for the past 780 years based on annual layer thickness and stable isotope analyses of a laminated stalagmite from southern Arabia. Our results show that monsoon variation over the past century is not outside of the range of the past 800 years. Decreasing monsoon rainfall over the past century is related to increasing sea surface temperature in the Indian Ocean. Spectral analyses of the record are dominated by cycles that are similar to those observed in records of solar activity on centurial timescales. Decadal to interannual cycles in the record appear to originate in the tropical Pacific Ocean.

本存档古气候学（Paleoclimatology）研究可通过世界古气候学数据服务（World Data Service for Paleoclimatology, WDS），从美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）下属的国家环境信息中心（National Centers for Environmental Information, NCEI）获取。该研究对应的NCEI研究分类为洞穴（Cave）类。数据集涵盖中东阿曼（Oman）地区的洞穴次生沉积物（speleothems）相关参数。其时间覆盖范围为以距今（before present, BP）为单位的日历年份时段，跨度从731至-46。如需了解参数与研究地点的详细信息，请查阅元数据（metadata）。使用该数据集时，请引用本研究。