"What Controls the Surface Ocean Iron Distribution? A Modeling Study".

“什么控制着表层海洋铁的分布？建模研究”。

• 批准号: 0350672
• 负责人: Michael Follows
• 金额: --
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2008-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0350672&HistoricalAwards=false
• 关键词: What; Controls; Surface; Ocean; Iron

ABSTRACTOCE- 0350672There is an increasing awareness of the key role of iron in ocean biogeochemical cycles, limiting primary production and potentially limiting export and nitrogen fixation. Due to increasing knowledge of distribution and speciation of oceanic iron, and of the processes that control it, it is timely to develop and examine numerical models of the ocean iron cycle. Numerical models provide one means by which to encapsulate the communities understanding of biogeochemical cycles and examine if this understanding is consistent with the available data (i.e. can the model reproduce the key features of the data). Such models may also be used to explore the sensitivities of the system to changes in forcing, parameterizations or parameter values.In this study, researchers at the Massachusetts Institute of Technology will continue the preliminary model studies by further developing, constraining, and exploring numerical models of the ocean iron cycle with the framework of a three-dimensional ocean GCM. The team of scientists will perform sensitivity tests to determine which are the most significant processes and how they respond to changing physical and biogeochemical forcing. Specifically, five chemical, physical and biological questions will be addressed: what are the optimal conditional stability constants and scavenging rates which bring the complexation based iron model into consistency with observed data; can the effects of surface photochemistry, the formation of colloids, and precipitation of iron be parameterized; do these processes have a significant role in setting the distribution and availability of iron; what is the impact of regionally varying availability (or solubility) of iron of aeolian origin; how sensitive is the surface distribution of iron and phosphorus to the veracity of the modeled ocean circulation; is the distribution of iron sensitive to details of the interactions of the ecosystem and multiple potentially limiting nutrients. As the culmination of this study a "best-shot" circulation and iron biogeochemistry model will be used to examine the role of time-varying physical and biogeochemical forcing and boundary conditions in modulating the ocean iron cycle. Finally, the team of scientists will examine the consequences for ocean biogeochemistry and air-sea gas fluxes.

铁在海洋生物地球化学循环中的关键作用越来越受到人们的关注，铁限制了初级生产，并可能限制出口和固氮。由于对海洋铁的分布和形态以及控制它的过程的了解越来越多，现在是开发和检查海洋铁循环的数值模型的时候了。 数值模型提供了一种手段，可以概括社区对地球化学循环的理解，并检查这种理解是否与现有数据一致（即模型能否再现数据的关键特征）。在这项研究中，研究人员在马萨诸塞州理工学院将继续初步的模式研究，进一步发展，限制，并探讨海洋铁循环的数值模式的框架下，一个三维的海洋GCM。 科学家团队将进行敏感性测试，以确定哪些是最重要的过程，以及它们如何应对不断变化的物理和地球化学强迫。 具体来说，五个化学，物理和生物学问题将得到解决：什么是最佳的条件稳定常数和清除率，使络合为基础的铁模型与观测数据的一致性，可以参数化的表面光化学，胶体的形成和沉淀的铁的影响，这些过程有一个重要的作用，在设置铁的分布和可用性;风成成因的铁的区域性变化的可用性（或溶解度）的影响是什么;铁和磷的表面分布对模拟的海洋环流的准确性有多敏感;铁的分布对生态系统和多种潜在限制性营养物的相互作用的细节有多敏感。 作为这项研究的高潮，一个“最佳”的循环和铁地球化学模式将被用来研究随时间变化的物理和地球化学强迫和边界条件在调制海洋铁循环的作用。最后，科学家团队将研究对海洋生物地球化学和海气通量的影响。