INVESTIGATING THE CAUSE AND STRUCTURE OF ABRUPT CLIMATE CHANGE EVENTS IN MARINE OXYGEN ISOTOPE STAGE 11

在过去的260万年里，地球的气候在寒冷和温暖的阶段之间摇摆，被称为冰期-间冰期循环。为了更好地理解气候反应，有必要寻找与今天条件相似的时期。其中一个时期，被称为海洋氧同位素阶段（MIS） 11（~430,000年前）越来越重要，因为；1)与今天相似的温暖期，以及2)格陵兰岛冰大量流失的时期。人们认为，格陵兰岛的淡水融化会扰乱海洋环流，从而导致北半球气候不稳定，而海洋环流通常会将温暖的海水带到高纬度地区。在MIS 11中，这种情况被称为“非树栖花粉期”，在整个欧洲都可以看到。这是一个气候突然变冷的时期，抑制了大树的生长。这一事件的原因尚不清楚。该博士项目旨在通过以下方式解决这一问题：(1)为记录这一事件的古湖盆提供高分辨率的温度和干旱记录(2)在北大西洋的多个海洋站点调查这一事件(3)确定导致这一事件的驱动因素。

Throughout the last 2.6 million years the earth's climate has oscillated between cold and warm phases, known as Glacial-Interglacial cycles. To better understand climatic responses, it is necessary to look for periods with similar conditions to present day. One period, known as Marine Oxygen Isotope Stage (MIS) 11 (~430,000 years ago) is of growing importance as; 1) a similar warm period to present day, and 2) a time of significant Greenland ice loss. Freshwater melt from Greenland is thought to cause climatic instability in the northern hemisphere by disrupting ocean circulation, which normally brings warm water to the higher latitudes. One such time where this occurred is referred to as "The Non-Arboreal Pollen Phase" in MIS 11, which is seen across Europe. This is a time where conditions abruptly became colder, inhibiting the growth of large trees. The cause of this event is not well understood. This PhD project aims to resolve this by (1) producing high-resolution temperature and aridity records for palaeolake basin(s) that record the event (2) investigating this event in multiple marine sites across the North Atlantic (3) establishing the driving factors responsible for this event.