Subtropical South African hydroclimate during the mid-Piacenzian Warm Period recorded by fynbos vegetation as a test case for climate model performance

上新世晚期3.264 ~ 3.025 Ma之间的偏岑子中期暖期（mWPW）被模型学家和古气候学家广泛研究，因为它为未来的变暖提供了一个地质模拟。数据模型的比较揭示了气候模型预测和古记录之间的不匹配：许多气候模型预测干燥的亚热带地区在温暖的时期，增强大气中的二氧化碳浓度，而mWPW的古记录表明湿润的亚热带地区。然而，现有的古记录集中在北方，没有高时间分辨率的记录南半球。为了填补这一空白，我提出了一个研究的轨道解决波动的mWPW南非亚热带水文气候登记的花粉从fynbos植被在深海海洋沉积物恢复西南从开普敦。将测试两种不同的强迫机制对亚热带南非气候的相对重要性。一方面，南非西海岸沿着海表温度变化的影响与南大西洋高压的强度和位置有关。另一方面，南极副热带锋的纬度变化和相关的西风漂移的影响。

The late Pliocene period between 3.264 and 3.025 Ma called mid-Piancenzian Warm Period (mWPW) is extensively studied by modelers and palaeoclimatologists because it presents a geologic analogue for future warming. Data-model comparisons reveal a mismatch between climate model predictions and palaeorecords: Many climate models predict drier subtropical regions during warm periods with enhanced atmospheric carbon dioxide concentrations, whereas palaeorecords of the mWPW indicate wetter subtropical regions. However, the available palaeorecords are concentrated on the northern hemisphere and there are no high temporal resolution records for the southern hemisphere. To fill this gap, I propose a study of orbital resolved fluctuations during the mWPW of South African subtropical hydroclimate registered by the pollen from fynbos vegetation in deep-sea marine sediments recovered southwest from Cape Town. The relative importance of two different forcing mechanisms on the climate of subtropical South African will be tested. On one hand, the influence of changes in sea surface temperatures along the west coast of South Africa related to the strength and position of the South Atlantic High. On the other hand, the effect of changes in the latitude of the Antarctic Subtropical Front and associated west wind drift.