Collaborative Research: Biological and physical controls on DMS production and emission during VOCALS

合作研究：VOCALS 过程中 DMS 产生和排放的生物和物理控制

• 批准号: 0743551
• 负责人: Barry Huebert
• 金额: $ 13.01万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0743551&HistoricalAwards=false
• 关键词: Collaborative; Research; Biological; physical; controls

Ocean-atmosphere exchange of the radiatively active biogenic trace gas, dimethylsulfide (DMS), is a major source of atmospheric sulfate aerosols: a key element of the global climate system. Climate affects this exchange by determining the physical-chemical characteristics of the upper ocean, thus shaping the marine planktonic ecosystem and the source strength of DMS. Attaining a more complete understanding of the interactions between the marine ecosystem and climate is an exciting challenge, which has barely begun to be explored. In this study, researchers at the Bigelow Laboratory for Ocean Sciences and the University of Hawaii at Manoa will examine the impact of light levels, sea surface temperature, upwelled nutrients, and winds on the production of DMS and its emission to the atmosphere. These critical linkages in the CLAW Hypothesis potentially determine whether this physical-biological feedback will be positive or negative. Does a modest change in PAR and UV increase or decrease DMS production and emission to the atmosphere? This will be studied in the context of complementary VOCALS projects studying atmospheric portions of CLAW: the oxidation of DMS to sulfate aerosols and their impact on clouds and the Earth?s radiation budget. Evaluating the magnitude and sign of such biotic feedbacks is of major societal and scientific importance. Specifically, the research will address the following themes in the South East Pacific (SEP) waters: (a) how far does the biogeochemical impact of upwelling on DMS production and air-sea flux extend offshore, (b) how do fewer clouds affect biological DMS production and SW concentrations, and (c) How do spatial gradients of SW DMS concentration and flux-controlling factors (e.g., winds) affect DMS fluxes to the atmosphere. The ultimate goal, in the synthesis phase of VOCALS REx and in collaboration with other participating investigators, would be to determine the significance of biotic feedbacks in controlling the radiation budget of the Southeast Pacific. The project will have several broader impacts. Training of one postdoctoral associate (Bigelow) and one graduate student (Hawaii) will be supported. In addition, the Bigelow PI will continue her participation in rural (local) K-8 programs as well as in the Grant Management Advisory Panel for the NSF ITEST grant Communities for Rural Education, Stewardship, and Technology led by the Island Institute (Rockland, ME). The Hawaii PI will use this data as examples (for problem sets and test questions) in his undergraduate and graduate level oceanography and atmospheric chemistry classes. Both PIs will participate in the VOCALS REx-coordinated broader outreach activities.

辐射活性生物微量气体二甲硫醚 (DMS) 的海洋与大气交换是大气硫酸盐气溶胶的主要来源，而硫酸盐气溶胶是全球气候系统的关键要素。气候通过决定上层海洋的物理化学特征来影响这种交换，从而塑造海洋浮游生态系统和DMS的源强度。更全面地了解海洋生态系统与气候之间的相互作用是一项令人兴奋的挑战，而这一挑战才刚刚开始被探索。 在这项研究中，毕格罗海洋科学实验室和夏威夷大学马诺阿分校的研究人员将研究光照水平、海面温度、上升的营养物质和风对 DMS 的产生及其向大气排放的影响。 CLAW 假说中的这些关键联系可能决定这种物理生物反馈是积极的还是消极的。 PAR 和 UV 的适度变化会增加还是减少 DMS 的产生和向大气的排放？这将在补充 VOCALS 项目的背景下进行研究，该项目研究 CLAW 的大气部分：DMS 氧化成硫酸盐气溶胶及其对云和地球辐射预算的影响。评估此类生物反馈的强度和迹象具有重大的社会和科学重要性。 具体来说，该研究将解决东南太平洋 (SEP) 水域的以下主题：(a) 上升流对 DMS 生产和海气通量的生物地球化学影响延伸到近海多远，(b) 较少的云如何影响生物DMS 产量和 SW 浓度，以及 (c) SW DMS 浓度的空间梯度和通量控制因素（例如风）如何影响进入大气的 DMS 通量。在 VOCALS REx 的合成阶段并与其他参与研究人员合作的最终目标是确定生物反馈在控制东南太平洋辐射预算中的重要性。 该项目将产生几个更广泛的影响。 将支持培训一名博士后助理（毕格罗）和一名研究生（夏威夷）。此外，毕格罗 PI 将继续参与农村（当地）K-8 项目以及由岛屿研究所（罗克兰、罗克兰、我）。 夏威夷 PI 将在他的本科和研究生水平的海洋学和大气化学课程中使用这些数据作为示例（用于问题集和测试问题）。两位 PI 将参加 VOCALS REx 协调的更广泛的外展活动。