Using high precision dissolved gas measurements to constrain the ocean carbon cycle

使用高精度溶解气体测量来限制海洋碳循环

• 批准号: 328290-2012
• 负责人: Hamme, Roberta
• 金额: $ 2.77万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=572146
• 关键词: Using; precision; dissolved; gas; measurements

The continuing increase in atmospheric carbon dioxide and its potential to affect our climate have made understanding the way carbon moves between different parts of the environment of utmost importance to our society. The ocean holds most of the carbon in our climate system, with the deep ocean naturally containing far higher carbon concentration than the surface due to both biological and physical processes. More carbon in the deep ocean means less in the atmosphere. My research program focuses on the biological and physical processes that send carbon to the deep ocean. The tools I use are high precision measurements of dissolved gases. First, we will make measurements of gases with no biological role (inert gases like neon, argon, krypton, and xenon) to determine how physical processes like temperature change, air-sea gas exchange, and atmospheric pressure affect any gas in the ocean. These measurements will be compared to the predictions of climate models to improve model processes for dissolved gases, including carbon dioxide. Second, we will make measurements of oxygen and its isotopes to determine the rate of ocean productivity (photosynthesis and respiration). These measurements will tell us the efficiency with which ocean ecosystems take up carbon dioxide and send it to the deep ocean in the form of particles. These measurements will also be compared to traditional methods based on incubations of seawater in bottles to understand the differences between methods and the uncertainties in each. Third, we will make measurements of dissolved nitrogen gas to determine the removal of nutrients like nitrate and ammonia from the ocean. The total amounts of nutrients in the ocean (essentially plankton fertilizer) can ultimately control ocean productivity, so we must understand the processes that remove nutrients from the ocean. Together these studies will help us to understand the way that carbon moves through the ocean and to better predict future changes. Better predictions of future ocean and atmospheric carbon dioxide concentrations will benefit Canadians by providing clearer criteria on which government representatives can make decisions regarding energy use and climate change mitigation strategies.

大气中二氧化碳的持续增加及其对气候的潜在影响使得了解碳在环境不同部分之间的流动方式对我们的社会至关重要。海洋拥有我们气候系统中的大部分碳，由于生物和物理过程，深海自然含有的碳浓度远高于表面。深海中的碳越多，大气中的碳就越少。我的研究项目侧重于将碳送到深海的生物和物理过程。我使用的工具是对溶解气体的高精度测量。首先，我们将测量没有生物作用的气体（惰性气体，如氖气、氩气、氪气和氙气），以确定温度变化、海气交换和大气压力等物理过程如何影响海洋中的任何气体。这些测量结果将与气候模式的预测进行比较，以改进溶解气体（包括二氧化碳）的模式过程。其次，我们将测量氧气及其同位素，以确定海洋生产力（光合作用和呼吸作用）的速率。这些测量将告诉我们海洋生态系统吸收二氧化碳并将其以颗粒形式发送到深海的效率。这些测量还将与传统的基于瓶中海水孵育的方法进行比较，以了解方法之间的差异以及每种方法的不确定度。第三，我们将测量溶解的氮气，以确定从海洋中去除硝酸盐和氨等营养物质。海洋中营养物质的总量（主要是浮游生物的肥料）最终可以控制海洋的生产力，所以我们必须了解从海洋中去除营养物质的过程。这些研究将帮助我们了解碳在海洋中的移动方式，并更好地预测未来的变化。更好地预测未来海洋和大气二氧化碳浓度将使加拿大人受益，因为它为政府代表就能源使用和减缓气候变化战略作出决策提供了更明确的标准。