Abrupt Climatic Changes During the Late Quaternary Monitored with Annual to Biennial Resolution in Santa Barbara Basin

Berger 9301438 作者建议使用南加州外圣巴巴拉盆地的层状沉积物，以年度分辨率研究已知或疑似快速气候变化的时期。有趣的时代包括“中世纪温暖时期”（公元950-1350年），气候最适期（5000年和8000年B. P.），冰消期和全冰期。将通过X射线照相术扫描岩心，以建立年表并确定感兴趣的级别;然后将对每个级别的代表几十年的剖面进行年度分辨率采样。厄尔尼诺间隔的发生，上升流的强度和初级生产力的水平，以及区域降水量将推断温度依赖的烯酮，稳定的碳同位素和氮，浮游植物化石的丰度和分类，以及纹层厚度。

Berger 9301438 The authors propose to study periods of known or suspected rapid climate change at an annual resolution, using laminated sediments from Santa Barbara Basin off Southern California. Times of interest include the "Medieval Warm Period" (950-1350 A.D.), the climatic optimum (5000 and 8000 years B.P.), the deglacial period and the full glacial. Cores will be scanned by Xradiography to set up a chronology and identify levels of interest; for each level a section representing a few decades will then be sampled with annual resolution. The occurrence of El Ni~io intervals, intensity of upwelling and levels of primary production, and regional precipitation will be inferred from temperature-dependent alkenones, stable carbon isotopes and nitrogen, abundance and taxonomy of phytoplankton fossils, and varve thickness.