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

在过去的260万年里，地球的气候一直在冷暖期之间振荡，这就是所谓的冰川-间冰期周期。为了更好地理解气候响应，有必要寻找与当今情况相似的时期。其中一个时期被称为海洋氧同位素阶段11(约43万年前)，其重要性与日俱增：1)与今天相似的暖期；2)格陵兰冰川显著消融的时期。来自格陵兰岛的淡水融化被认为通过扰乱海洋循环而导致北半球的气候不稳定，而海洋循环通常会将温暖的水带到更高的纬度。在MIS11中，这种情况发生的一个时期被称为“非乔木花粉期”，这在整个欧洲都能看到。这是一个条件突然变冷的时期，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)制作记录这一事件的古湖盆地(S)的高分辨率温度和干旱记录(2)在北大西洋的多个海洋地点调查这一事件(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.