Collaborative Research: The Cariaco Basin Oceanographic Time Series Program

该合同将为三家美国机构——南佛罗里达大学、南卡罗来纳大学哥伦比亚分校和石溪大学——提供三年多的支持，用于位于委内瑞拉大陆边缘缺氧的卡里亚科盆地的卡里亚科盆地海洋时间序列。CARIACO自1995年11月以来持续运作，其科学目标是了解水文、浮游生物群落组成、初级生产、微生物活动、陆源输入、颗粒和其他通量以及水柱中元素循环的其他过程之间的关系，以及它们的变化如何在海底沉积物中保存下来。该项目致力于为海洋碳和生物地球化学（OCB）以及古气候研究界提供服务，通过在卡里亚科盆地维持一个观测设施，提供核心观测和样本，并促进研究人员进入一个独特的、世界闻名的热带大陆边缘环境。加勒比合作组织的一个中心原则是，那里产生的数据流有助于解释海洋碳通量和全球气候变率。了解影响下沉物质的过程是理解“生物碳泵”以及将物质从海洋表面和邻近陆地转移到海底的过程的关键。由于卡里亚科盆地仅在浅层（140米）以上与邻近的加勒比海交换地表水，因此在~250米以下普遍存在缺氧。这些条件为国际社会研究全新世和晚更新世气候变化提供了良好的变异沉积记录。OCB社区认识到，由于自然气候变率和人类活动之间的相互作用，我们正在接近全球生物圈的“状态转移”。像CARIACO这样的海洋时间序列在记录和评估海洋生态系统对气候细微变化作出反应的机制方面发挥着关键作用。事实上，研究小组已经记录了过去17年来卡里亚科盆地的巨大变化，这些变化反映了更大空间和时间尺度上的变化。他们将这些生态系统和生物地球化学变化归因于热带辐合带的北移。更广泛的影响：加勒比海洋时间序列的成功归功于与委内瑞拉、美国和其他国家的科学家建立的强有力的合作。它有助于发展一个日益增长的全球观测站，其重点是测量生态过程和了解地球系统大尺度变化的影响。CARIACO是一个与国际碳循环和更广泛的海洋学研究相关的IGBP-LOICZ项目。通过提供气候代理来提高过去气候评估的准确性，CARIACO直接解决了CLIVAR和PAGES倡议的世界气候研究计划和国际地圈-生物圈计划的目标。该科学还有助于理解生态系统变化的社会经济影响，例如该地区过去十年中沙丁鱼渔业的崩溃和灾难性的天气事件。加勒比促进国际科学合作。委内瑞拉为当地科学家参与这一联合努力提供的资助是继续开展这一项目的一个重要激励。加勒比共同体对拉丁美洲的技术转让和能力建设产生了重大影响，为该区域的科学家提供了参与一个处理与全球有关的问题的项目的机会。加勒比合作组织还使美国学生和科学家接触到国际研究界以及加勒比和拉丁美洲的文化。研究小组打算继续积极努力，在加勒比加勒比地区、BATS、HOT和其他各种OCB项目之间建立科学和技术联系。

This award will provide three more years of support to three U.S. institutions -- University of South Florida, University of South Carolina at Columbia, and Stony Brook University -- for the CARIACO Basin Ocean Time-Series, located in the anoxic Cariaco Basin on the Venezuelan continental margin. In continuous operation since November, 1995, the scientific goal of CARIACO is to understand the relationships between hydrography, plankton community composition, primary production, microbial activity, terrigenous inputs, particle and other fluxes, and other processes of element cycling in the water column, and how their variation is preserved in seafloor sediments. The program strives to serve the ocean carbon and biogeochemistry (OCB) and the paleoclimate research communities by maintaining an observing facility in the Cariaco Basin that provides core observations and samples, and facilitates researcher access to a unique, world-renown tropical continental margin setting. A central tenet of CARIACO is that the data stream produced there aids in the interpretation of oceanic carbon fluxes and global climate variability. Understanding processes that affect sinking material is key to understanding the "biological carbon pump" and processes that transfer materials from the surface ocean and adjacent land to the bottom. Since the Cariaco Basin only exchanges surface waters with the adjacent Caribbean Sea above a shallow ( 140 m) sill, anoxia prevails below ~250 m. These conditions preserve an excellent varved sediment record that is used by the international community to study Holocene and late Pleistocene climate change. The OCB community recognizes that we are approaching a "state shift" in the global biosphere due to interactions between natural climate variability and human activities. Ocean time series like CARIACO play a critical role in documenting and evaluating the mechanisms whereby marine ecosystems respond to subtle changes in climate. Indeed, the research team has documented dramatic changes in the Cariaco Basin over the past 17 years that reflect transformations over larger space and time scales. They attribute many of these ecosystem and biogeochemical changes to a northward migration of the Intertropical Convergence Zone.Broader impacts: The CARIACO Ocean Time-Series owes its success to strong collaborations established with scientists in Venezuela, the US, and other countries. It contributes to development of a growing global observatory focused on measuring ecological processes and understanding impacts of large-scale changes in the Earth system. CARIACO is an IGBP-LOICZ program relevant to international carbon cycle and broader oceanographic research. By providing climate proxies that improve the accuracy of past climate assessments, CARIACO directly addresses the goals of the CLIVAR and PAGES initiatives of the World Climate Research Programme and the International Geosphere-Biosphere Programme. The science also helps understand socio-economic impacts of ecosystem variability, such as the collapse of the sardine fishery and catastrophic weather events seen in the last decade in the region. CARIACO nurtures international scientific cooperation. Venezuelan funding for local scientists to participate in this joint effort is an important incentive to continue this program. CARIACO has had a significant impact on technology transfer and capacity building in Latin America, by providing regional scientists with opportunities to participate in a project that addresses issues of global relevance. CARIACO also exposes U.S. students and scientists to an international research community and to the cultures of the Caribbean and Latin America. The research team intends to continue proactive efforts to develop scientific and technical links between CARIACO, BATS, HOT, and various other OCB Program efforts.