Tipping elements and thresholds for extreme climate events in the Indian Summer Monsoon (ISM) realm (TISUR) IP3: Ecological regime shifts in response to monsoon dynamics and anthropogenic activities

印度夏季季风 (ISM) 领域 (TISUR) 极端气候事件的临界要素和阈值 IP3：响应季风动态和人类活动的生态状况变化

• 批准号: 416748683
• 负责人: Dr. Martina Stebich
• 金额: --
• 依托单位: Forschungsstation für Quartärpaläontologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/416748683?language=en
• 关键词: Tipping; elements; thresholds; extreme; climate

The Indian Summer Monsoon (ISM) affects the lives of over a billion strong population, yet remains one of the least understood components of the global climate system. While the mid- and late-Holocene weakening of the ISM in response to decreasing solar insolation is well established, the spatiotemporal influence of tipping elements (e.g. ENSO, THC) in triggering extreme climate events and ecological regime shifts in the ISM realm is not well understood. Reconstructing major ISM shifts preserved in palaeoenvironmental archives is essential to advance our understanding of its interaction with known tipping elements and contribute towards identifying the mechanistic principles underlying climate shifts and extremes. In this coordinated effort we aim to develop a comprehensive picture of mid- to late Holocene climate variability over the ISM realm using a multiproxy approach on three lakes (sediment cores) from climatically sensitive regions. Four closely interrelated proposals aim to (i) reconstruct palaeoenvironmental changes, identify tipping points and regime shifts at each site; (ii) provide information on ecosystem response in different climate settings; and (iii) undertake transregional comparison using modern numerical methods to disentangle tipping elements driving ISM shifts and extreme events. The results of these studies can potentially help in predicting and mitigating the ecological and economic impact of future climate change in vulnerable regions.This proposed project addresses mid to late Holocene dynamics of vegetation, climate and human activity based on detailed pollen analyses on lacustrine sediments of the Manasbal Lake (N India) and the Khecheopalri Lake (NE India). We especially focus on the identification of threshold responses and regime shifts in the studied terrestrial and aquatic ecosystems. Furthermore, investigations on modern surface pollen spectra will be carried out in order to capture the relationship between the modern pollen assemblages, vegetation, climate and human pressure and thus to improve the interpretation of the fossil pollen record.

印度夏季风(ISM)影响着超过十亿人口的生活，但仍然是全球气候系统中最不被理解的组成部分之一。尽管中、晚全新世ISM对太阳辐射减弱的响应已得到很好的证实，但在ISM领域引发极端气候事件和生态系统变化的倾动元素(如ENSO、THC)的时空影响还不是很清楚。重建保存在古环境档案中的主要ISM变化对于促进我们对其与已知倾倒元素的相互作用的理解至关重要，并有助于确定气候变化和极端事件背后的机制原理。在这项协调努力中，我们的目标是利用气候敏感地区的三个湖泊(沉积物岩芯)的多重代理方法，对ISM领域的中晚期全新世气候变异性进行全面的描述。四项密切相关的建议旨在：(1)重建古环境变化，确定每个地点的转折点和制度转变；(2)提供关于不同气候环境下生态系统反应的信息；(3)利用现代数值方法进行跨区域比较，以理清驱动ISM转变和极端事件的转折因素。这些研究的结果可能有助于预测和减轻未来气候变化对脆弱地区的生态和经济影响。这个拟议的项目基于对马纳斯巴尔湖(印度北部)和赫希奥帕里湖(印度东北部)湖泊沉积物的详细花粉分析，研究了全新世中后期的植被、气候和人类活动的动态。我们特别关注在所研究的陆地和水生生态系统中阈值响应和制度转变的识别。此外，还将开展现代地表花粉谱研究，以捕捉现代花粉组合与植被、气候和人类压力之间的关系，从而提高对化石花粉记录的解释。