Basic research for the technological advancement of the determination of the oceanic CO_2 variability

海洋CO_2变化测定技术进步的基础研究

• 批准号: 16310018
• 负责人: ISHII Masao
• 金额: $ 10.24万
• 依托单位: Meteorological Research Institute, Japan Meteorological Agency
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16310018/
• 关键词: alkalinity; hexafluorosulfide; chemical tracer

We have designed and built a new automated spectrophotometric system for precise total alkalinity analysis in seawater. We also made and improved software to properly control it. In June-July 2005, we participated in a cruise of JMA's R/V Ryofu-maru that sailed western North Pacific along, 165^ΩE between 50^ΩN and 28^ΩN across the transition zone between western sub arctic gyre and subtropical gyre, and collected seawater samples at 18 hydrographic stations from various depths down to 1000m. After the cruise we analyzed their total alkalinity and demonstrated that the new system is capable of high-precision analysis with the precision of ±2 μmol kg^<-1> (less than 1/1000). In addition, from the change in the property-property plots between total dissolved inorganic carbon (DIC) and alkalinity, we evaluated that DIC in the upper layer of this zone has increased about 15 μmol kg^<-1> during the last 13 years due to the uptake of the increasing atmospheric CO_2.We have also designed and built a system and a sampling bottle to analyze the back-ground-level hexafluorosulfide (SF_6) dissolved in seawater. We succeeded in lower the detection limit to 0.015 femto(10^<-15>)mol/kg after investigating the optimum conditions of detector-temperature, flow rate of carrier gas, and so on. We also prepared a standard gas for low level SF_6 in a finely ground 10L aluminum-alloy cylinder, and proved that its concentration is stable at least for 9 months after preparation. In the western North Pacific along 137^ΩE during the JMA's R/V Ryofu-maru cruise in October 2006, we collected seawater samples from various depths and succeeded in obtaining vertical profiles of SF_6 that showed a maximum concentration of 1.1 femtomol/kg in the subsurface layer.

我们已经设计并建立了一个新的自动分光光度法系统，以精确的海水总碱度分析。我们还制作并改进了软件以正确控制它。 2005年6月至7月，我们参加了JMA的R/V Ryofu-Maru巡游，该巡航为北太平洋西部挽救了165^ωe，在50^ωn和28^ωn之间，整个北极北极子Gyre和亚热带Gyre之间的过渡区域之间的过渡区域，并收集了来自各种水平的18个水文站的Seawater Samples，从各种深度降至1000000000000亿。巡航后我们分析了它们的总碱度，并证明了新系统能够以±2μmolkg^<-1>的精度进行高精度分析（小于1/1000）。 In addition, from the change in the property-property plots between total dissolved inorganic carbon (DIC) and alkalinity, we evaluated that DIC in the upper layer of this zone has Increased about 15 μmol kg^<-1> during the last 13 years due to the uptake of the increasing atmospheric CO_2.We have also designed and built a system and a sampling bottle to analyze the back-ground-level hexafluorosulfide （SF_6）溶解在海水中。在研究检测器 - 温度的最佳条件，载气的流速等之后，我们成功地将检测限制到0.015 fem（10^<-15>）mol/kg。我们还准备了在精细的10L铝合金缸中低水平SF_6的标准气体，并证明其浓度至少在制备后至少在9个月内保持稳定。在2006年10月的JMA R/V Ryofu-Maru巡游中，在北太平洋沿137^ωe中，我们从各个深度收集了海水样品，并成功地获得了SF_6的垂直谱图，在地下层中显示最大浓度为1.1 fomtomol/kg。