Collaborative Research: Disentangling physical and biological controls on Indian Ocean carbon storage during the last glacial-interglacial transition

合作研究：理清末次冰期-间冰期过渡期间印度洋碳储存的物理和生物控制

基本信息

批准号：
2002642
负责人：
Elisabeth Sikes
金额：
$ 12.86万
依托单位：
Rutgers University New Brunswick
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2024-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2002642&HistoricalAwards=false
关键词：
Collaborative Research Disentangling physical biological

项目摘要

Evidence suggests more carbon dioxide was stored in deep ocean waters during the last ice age and released to the atmosphere as the Earth warmed. There are several ways that this might happen. Carbon dioxide could be released when the total amount of algae in ocean waters decreases after the last ice age. Or the amount of carbon dioxide stored in the deeper ocean waters could change with differing pathways of deep currents. Recent work suggest the Indian Ocean might play an important role in one or both of these processes. Newly collected sediment cores collected from the Indian Ocean will be examined for subtle changes in the chemistry that will provide scientists a way to document how carbon dioxide moves between the oceans and atmosphere over long periods of time. The social media platform of the American Museum of Natural History will be used to produce short video segments and visualizations of ocean circulation and climate to share with educators and the general public. The question of physical versus biological controls of CO2 sequestration in the glacial ocean remains unresolved after decades of research. During glaciations, changes in thermohaline circulation, Southern Ocean ventilation, and nutrient utilization are all believed to have played an important role in reducing atmospheric CO2. An improved understanding of the different roles of biological transfer versus physical transfer of CO2 requires examining multiple water masses in multiple ocean basins. The scientific objective is to reconstruct the magnitude and mechanisms driving carbon storage in the southern Indian Ocean by determining the temporal evolution and vertical distribution of Delta14C and oxygenation (using quantitative proxies: Delta-delta13Cwuel-globo, and alkenone preservation) in Indian Ocean interior water masses across the last glacial-interglacial transition. These proxies have been chosen to distinguish between the rate of water mass circulation and respiration-driven CO2 accumulation to assess the roles these mechanisms played in CO2 sequestration. The use of multiple sediment cores across latitude and longitude has been fundamental in determining that critical indicators of oceanic CO2 storage (Delta14C and oxygenation) differed substantially in the Atlantic and Pacific through time. Work proposed here will fill a substantial gap in our knowledge by making use of the first new core material from the Southern Indian Ocean in nearly 30 years. We have selected a suite of three suitable cores from depths (1,118 to 3,164 m) that are bathed by the major interior water masses that reflect both respiration and circulation driven CO2 storage in the region today. Results created here will be the first from this area using these techniques to determine the magnitude and mechanisms of Southern Indian Ocean CO2 storage.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

有证据表明，在最后一个冰河时代，将更多的二氧化碳存储在深海水域中，并随着地球变暖而释放到大气中。有几种可能发生的方式。当上一个冰河时代后，海水中的藻类总量减少时，二氧化碳可以释放。或在深海水域中储存的二氧化碳量可能会随着深水的不同途径而变化。最近的工作表明，印度洋可能在这一过程中的一个或两个过程中发挥重要作用。从印度洋收集的新收集的沉积物核心将检查化学的细微变化，这将为科学家提供一种记录二氧化碳在长时间内如何在海洋和大气之间移动的方法。美国自然历史博物馆的社交媒体平台将用于制作简短的视频细分市场和海洋流通和气候的可视化，以与教育者和公众分享。经过数十年的研究，冰期海洋中二氧化碳隔离的物理与生物控制问题仍然无法解决。在冰川期间，据信，热盐循环，南洋通风和营养利用的变化都在减少大气二氧化碳中发挥了重要作用。对二氧化碳的生物转移与物理转移的不同作用的改进，需要检查多个海盆中的多种水质量。科学的目标是通过确定delta14c和氧合的时间演化和垂直分布（使用定量代理：delta-delta13cwuel-globo，以及烯酮保存），在印度海洋内部水群中，跨胶状内部的质量跨度，来重建印度洋南部的幅度和机制。这些代理已被选择以区分水质量循环速率和呼吸驱动的二氧化碳积累，以评估这些机制在CO2隔离中起的作用。跨越纬度和经度的多个沉积物核心在确定海洋二氧化碳储存的关键指标（Delta14c和氧合）的关键指标在随着时间的流逝中有很大差异。在这里提出的工作将在近30年内利用印度洋南部的首个新核心材料来填补我们的知识的巨大空白。我们已经选择了由深度（1,118至3,164 m）的三个合适核心组成的套件，这些核心是由主要的内部水质量沐浴的，这些内部水肿反映了当今该地区的呼吸和循环驱动的二氧化碳存储。此处创建的结果将是该领域的第一个使用这些技术来确定南部印度洋二氧化碳存储的幅度和机制。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，被认为值得通过评估。