Time Series Particle Flux Measurements in the Sargasso Sea

考虑到温室气体增加对全球气候的人为扰动，了解年际和年代际时间尺度上的海洋变率具有广泛的兴趣和日益重要的意义。可以肯定的是，海洋生态系统将受到气候模式变化的影响，因此必须对海洋对可能的气候变化情景的反应进行评估和建模。这需要对海洋及其生物群如何自然地对气候和环境强迫变量作出反应有一个基本的了解。海洋观测是必要的第一步。长期研究对我们了解海洋如何运作的贡献是巨大而深远的。然而，这样的研究是极其罕见的——尤其是那些以生物地球化学为重点的研究。自1978年以来，海洋通量计划（OFP）连续测量了深马尾藻海的颗粒通量。到目前为止，28年的OFP时间序列是同类中最长的，并且在关注深海方面是独一无二的。OFP在“生物泵”中产生了一种独特的，尽管是“经过编辑的”，时间变化的记录。“生物泵”在这里是一个宽泛的术语，用于描述物质从表层向深海的转移。OFP为深海的季节性以及深海通量与上层海洋过程之间的紧密耦合提供了第一个直接证据。它提供了明确的证据，表明中上层水域中通量的生物再处理和悬浮物的清除强度。该记录记录了深层通量的年际和较长的变化，以及由中尺度变率和气象强迫之间的相互作用驱动的较短期波动。时间序列变得足够长，可以开始研究多年来盆地尺度气候强迫的变异性，例如北大西洋涛动。有了这笔资金，百慕大生物研究站和海洋生物实验室的研究人员将继续研究这一独特而基础的海洋学时间序列。随着记录的延长，我们能够更好地观察到气候和海洋功能之间相互作用的波动。在百慕大，OFP、百慕大大西洋时间序列（BATS）和百慕大系泊试验台（BTM）这三个相互协调和互补的时间序列与新的海洋技术同时出现，为研究海洋物理、生物、化学和物质通量之间的耦合相互作用以及这些相互作用如何与大气和气候强迫联系起来提供了无与伦比的机会。该项目预计将产生一系列更广泛的影响：(1)系统的、长期的生物地球化学观测，如OFP提供的观测，对于了解海洋的自然变异至关重要，并为解释未来可能的气候变化情景的影响提供了一个参考点。(2)以前的NSF小组将OFP项目称为“社区资源”。该项目将继续与研究人员和学生共享其资源，包括样品材料、数据、辅助船舶时间和系泊平台的使用，以使社区以极低的成本进行各种调查成为可能。(3) OFP样本档案是不可多得的宝藏。收集的样品材料将继续对当前和未来的生物地球化学和气候研究具有宝贵价值。(4) OFP提供的教育经验将在关键时刻拓宽许多年轻研究人员的研究经验和视野。特别有价值的是有机会直接参与观测海洋学、时间序列研究和百慕大天文台的综合活动。

ABSTRACTOCE-0623505Understanding ocean variability over interannual and decadal time-scales is of widespread interest and increasing relevance given the concerns over anthropogenic perturbations on global climate due to increases in greenhouse gases. It is certain that ocean ecosystems will be affected by altered climate patterns, and an imperative exists to assess and model the ocean's response to possible climate change scenarios. This requires a fundamental understanding of how the ocean and its biota naturally respond to climate and environmental forcing variables. Ocean observation is a necessary first step. The contributions of long-term studies to our knowledge of how the ocean works are numerous and far-reaching. Yet, such studies are exceedingly rare- especially those with a biogeochemical focus. Since 1978, the Oceanic Flux Program (OFP) has continuously measured particle fluxes in the deep Sargasso Sea. The 28 year OFP time-series is, by far, the longest of its kind and unique in its focus on the deep ocean. OFP has produced a unique, albeit "edited", record of temporal variability in the "biological pump", a term loosely applied here to material transfer from the surface to the deep ocean. The OFP provided the first direct evidence for seasonality in the deep ocean and the tight coupling between deep fluxes and upper ocean processes. It has provided clear evidence of the intensity of biological reprocessing of flux and scavenging of suspended material in mesopelagic waters. The record has documented interannual and longer variations in deep fluxes and shorter term fluctuations driven by the interactions between mesoscale variability and meteorological forcing. The time-series is becoming long enough to begin study of variability in terms of multiyear basin-scale climatic forcing, such as the North Atlantic Oscillation. With funding from this award, researchers at the Bermuda Biological Station for Research and the Marine Biological Laboratory will continue operation of this unique and fundamental oceanographic time-series. As the record gets longer, we are better able to put into perspective the observed fluctuations in terms of the interplay between climate and ocean functioning. The concurrence of three co-coordinated and complementary time-series at Bermuda -- the OFP, the Bermuda Atlantic Time-Series (BATS) and the Bermuda Testbed Mooring (BTM) --and new ocean technology presents unparalleled opportunities to study the coupled interactions among ocean physics, biology and chemistry and material fluxes, and how these in turn are linked to atmospheric and climatic forcing. This project is expected to have a number of broader impacts: (1) Systematic, long-term biogeochemical observations, such as those provided by the OFP, are essential to gain an understanding of natural oceanic variability and to provide a reference point in which to interpret the repercussions of possible future climate change scenarios. (2) Previous NSF panels have termed the OFP program a "community resource". The project will continue to share its resources- sample material, data, ancillary shiptime, and use of the mooring platform- with researchers and students to make possible a diverse range of investigations at a very low cost to the community. (3) The OFP sample archive is a rare treasure. The sample material to be collected will continue to be invaluable for current and future biogeochemical and climate studies. (4) Educational experiences provided by the OFP will broaden the research experiences and horizons of many young research investigators at a critical juncture. Of particular value are opportunities to become directly involved with observational oceanography, time-series research and integrated activities of the Bermuda Observatory.