A low cost disposable instrument for vertical profile measurements of atmospheric CO2

该提案旨在评估目前用于商业和家用锅炉系统泄漏检测的技术的可行性，以提供一种低成本（50-100欧元）基于一次性探空仪的仪器，用于测量二氧化碳的垂直剖面。如果具备适当的测量特征，这种仪器组成的小型网络可对全球大气二氧化碳通量监测作出重大贡献，增加从目前地基和卫星方法获得的信息，对了解和预测未来气候可能产生重大影响。该项目的主要交付成果将是一个针对二氧化碳剖面测量进行优化的原型仪器，以及生产二氧化碳探空仪器的设计和性能规范。这种方法的新颖之处在于，它将在远高于背景环境条件的浓度下得到验证的技术适应于高层大气中未经试验的环境，而高层大气需要更高的精度。技术方法：非色散红外（NDIR）吸收光谱学该技术的基础是吸收光谱学，用比尔-朗伯定律表示。这种技术的优点是，它有一个基本的校准，基于已知或可计算的吸收截面。在这种情况下，使用光谱滤波器而不是色散元件来定义光谱通带，因此称为“非色散”。CO2是用其以2349 cm-1为中心的基本振动-旋转吸收带测量的。该研究计划将分四个阶段进行：1)传感器设计的优化2)优化原型仪器的构建3)实验室和剖面模拟仪器的表征4)生产CO2探空仪器的设计和性能规范。

This proposal is to assess the feasibility of adapting technology currently used for leak detection in commercial and domestic boiler systems to provide a low cost (50-100 euro) disposable sonde based instrument for measuring vertical profiles of CO2. With suitable measurement characteristics, a small network of such instruments could contribute significantly to global atmospheric CO2 flux monitoring, adding to the information obtainable from the current ground-based and satellite based approaches, with potentially significant implications for understanding and predicting future climate,. The principal deliverable of the project will be a prototype instrument optimised for CO2 profile measurements, and the design and performance specification for a production CO2 sonde instrument. The novelty of this approach is the adaptation of technology proven at concentrations well above background ambient conditions to the untried environment of the upper atmosphere where far higher precision is required. Technological approach: non dispersive infra-red (NDIR) absorption spectroscopy The basis of the technology is absorption spectroscopy, as expressed by the Beer-Lambert law. The advantage of this technique is that it has a fundamental calibration, based on known or calculable absorption-cross-sections. In this case a spectral filter rather than a dispersing element is used to define the spectral passband, hence the term 'non-dispersive'. CO2 is measured using its fundamental vibration-rotation absorption band centred at 2349 cm-1. The research program will take place in four phases: 1) Optimisation of sensor design 2) Construction of optimised prototype instrument 3) Laboratory and profile simulation instrument characterisation 4) Design and performance specification for a production CO2 sonde instrument.