Climate and environmental change in the Andaman Sea since the late Little Ice Age: Sea surface temperature, hydroclimate, and coral response to thermal stress in the northeastern Indian Ocean (IndOC-E)

小冰期晚期以来安达曼海的气候和环境变化：印度洋东北部海面温度、水文气候和珊瑚对热应力的响应 (IndOC-E)

• 批准号: 468644633
• 负责人: Dr. Thomas Felis
• 金额: --
• 依托单位: Zentrum für Marine Umweltwissenschaften (MARUM)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/468644633?language=en
• 关键词: Climate; environmental; change; Andaman; Sea

This project contributes towards a better understanding of tropical marine climate variability and its impact on coral reef ecosystems in a warming world, by quantifying climatic and environmental changes during the warming from the pre-instrumental period to the early 21st century on timescales relevant for society. These are major aims of the Priority Programme “Tropical Climate Variability and Coral Reefs” (SPP 2299). The project will reconstruct marine climate and environmental change in the northeastern Indian Ocean since the late Little Ice Age at ultra-high resolution, by analysing isotopic and geochemical proxies in shallow-water coral skeletons. It is proposed to generate reconstructions of sea surface temperature, hydrology (hydroclimate), and coral response to thermal stress back to the early 1800s (or even early 1700s) at monthly resolution from Porites corals of the southern Andaman Sea (Thailand). A site not strongly affected by marine heatwaves because of the mitigating effect of cooling by internal waves will provide proxy records of sea surface temperature and hydrology (hydroclimate), based on paired measurements of Sr/Ca and 18O. Another site experiencing the unabated influence of heatwaves will provide a proxy record of coral response to thermal stress events, based on anomalous signatures in measurements of Sr/Ca, 18O, Mg/Ca, 13C, and growth patterns. The reconstructions will enable to study the interplay of different El Niño flavours, the Indian Ocean Dipole, volcanic eruptions, and large amplitude internal waves in modulating variability and extremes of Andaman Sea temperatures and hydrology since the late Little Ice Age, with implications for coral growth, resilience, and Asian monsoon hydrological extremes. Furthermore, the validation of historical sea surface temperature products for time intervals of sparse observations or method changes, the occurrence of a prominent early 19th century cold interval in tropical Indian Ocean temperature, and the potential for reconstructing Indian Ocean Dipole events will be explored. The reconstructions will enable to explore if Andaman Sea corals were exposed to thermal stress events during past centuries and if ecological memory, resulting from extreme northeastern Indian Ocean warmings of the past such as the very strong 1877/78 El Niño event, lead to higher temperature tolerance during thermally-induced stress events of recent decades. Together with a companion project, Indian Ocean warming and interannual variability since the late Little Ice Age, basin-scale differences, and relationships with global warming and tropical Pacific interannual variability will be studied at the basin’s northeastern and western rim.

该项目通过在与社会相关的时间尺度上量化从仪器使用前到世纪初变暖期间的气候和环境变化，有助于更好地了解热带海洋气候变异及其对全球变暖中的珊瑚礁生态系统的影响。这些是“热带气候多变性和珊瑚礁”优先方案（SPP 2299）的主要目标。该项目将通过分析浅水珊瑚骨骼中的同位素和地球化学代用指标，以超高分辨率重建小冰期晚期以来印度洋东北部的海洋气候和环境变化。建议从安达曼海南部（泰国）的滨珊瑚珊瑚中以每月分辨率重建海面温度，水文（水文气候）和珊瑚对热应力的反应，可以追溯到19世纪初（甚至18世纪初）。由于内波冷却的缓解作用，受海洋热浪影响不大的站点将根据Sr/Ca和18 O的成对测量提供海面温度和水文（水文气候）的代用记录。另一个网站经历了有增无减的热浪的影响，将提供一个代理记录的珊瑚热应力事件的反应，根据测量的Sr/Ca，18 O，Mg/Ca，13 C和生长模式的异常签名。重建将能够研究不同的厄尔尼诺现象，印度洋偶极子，火山爆发和大幅度内波的相互作用，以调节自小冰期后期以来安达曼海温度和水文的变化和极端情况，对珊瑚生长，恢复力和亚洲季风水文极端情况产生影响。此外，还将探讨在观测稀疏或方法改变的时间间隔内验证历史海表温度产品、在热带印度洋温度中出现一个显著的世纪早期冷间隔以及重建印度洋偶极子事件的可能性。这些重建将有助于探索安达曼海珊瑚在过去几个世纪中是否暴露于热应力事件，以及过去东北印度洋极端变暖（如1877/78年非常强烈的厄尔尼诺事件）导致的生态记忆是否在近几十年的热应力事件中导致更高的温度耐受性。连同一个配套项目，印度洋变暖和年际变化，因为小冰期后期，流域规模的差异，以及与全球变暖和热带太平洋年际变化的关系将在盆地的东北和西部边缘进行研究。