2023-01-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/699600Climate variability, either in the form of extreme events (e.g., heat waves) or interannual oscillations in tropical oceans such as El Nino-Southern Oscillation (ENSO), can wreak havoc on society in the Indo-Pacific realm. A robust mechanistic understanding and the ability to predict future climate variability is critical for mitigation and adaptation in response to climate change. Towards this end, past archives of climate variability and extreme events may help to constrain the possible range and frequency of future climate variability. However, reconstruction of climate variability is not trivial due to inherent limitations of natural paleoclimate archives. One emerging quantitative approach is Individual Foraminifera Analysis (IFA). Planktic foraminifera has a lifespan of three to four weeks, therefore the geochemical signal (e.g. Mg/Ca reflecting temperature) in each shells record a snapshot of the seawater conditions during their lifespan. Collectively, the distribution of the geochemical signal recorded by these shells within a population provide an estimate of climate variability. Despite their usefulness, the IFA protocol especially for Mg/Ca paleothermometry remains technically challenging, and is thus far limited to several laboratories in Europe and North America. To follow-up on progress made during the 1st phase of the project (2020–2022), in the next phase (2023–2025) we plan to apply the newly developed IFA method on 3 types of samples spanning different timescales, namely (1) depth-stratified plankton net samples (0–500 m) which provide a temporal snapshot during the collection period, (2) sediment trap samples which provide insights into weekly to monthly variability and (3) sediment core samples spanning the last glacial cycle (0– 25 kyr). This unique collection of plankton net, sediment trap and core samples make it possible to examine the spatial and temporal changes in IFA variability, and further shed light on various hydrographic and sedimentation processes that govern the IFA-temperature variability in sediments. Climate variability, either in the form of extreme events (e.g., heat waves) or interannual oscillations in tropical oceans such as El Nino-Southern Oscillation (ENSO), can wreak havoc on society in the Indo-Pacific realm. A robust mechanistic understanding and the ability to predict future climate variability is critical for mitigation and adaptation in response to climate change. Towards this end, past archives of climate variability and extreme events may help to constrain the possible range and frequency of future climate variability. However, reconstruction of climate variability is not trivial due to inherent limitations of natural paleoclimate archives. One emerging quantitative approach is Individual Foraminifera Analysis (IFA). Planktic foraminifera has a lifespan of three to four weeks, therefore the geochemical signal (e.g. Mg/Ca reflecting temperature) in each shells record a snapshot of the seawater conditions during their lifespan. Collectively, the distribution of the geochemical signal recorded by these shells within a population provide an estimate of climate variability. Despite their usefulness, the IFA protocol especially for Mg/Ca paleothermometry remains technically challenging, and is thus far limited to several laboratories in Europe and North America. To follow-up on progress made during the 1st phase of the project (2020–2022), in the next phase (2023–2025) we plan to apply the newly developed IFA method on 3 types of samples spanning different timescales, namely (1) depth-stratified plankton net samples (0–500 m) which provide a temporal snapshot during the collection period, (2) sediment trap samples which provide insights into weekly to monthly variability and (3) sediment core samples spanning the last glacial cycle (0– 25 kyr). This unique collection of plankton net, sediment trap and core samples make it possible to examine the spatial and temporal changes in IFA variability, and further shed light on various hydrographic and sedimentation processes that govern the IFA-temperature variability in sediments.印度太平洋地區; 個體有孔蟲分析; 全新世; 末次冰盛期; 氣候變異;Indo-Pacific realm; Individual foraminifera analysis; Holocene; Last Glacial Maximum; Climate variability