The potential for carbon dioxide (CO2) in the atmosphere to influence global surface temperatures was first recognized in the mid-nineteenth century. Even so, high-precision measurements of atmospheric CO2 concentration were not commenced until the International Geophysical Year (1957–8), following concerns of the climatic impact of increased use of fossil fuels and the concomitant release of CO2 into the atmosphere. In Australia, an early (1960s–70s) interest in the high-precision measurement of CO2 concentration was stimulated by a study of the photosynthesis and respiration of awheat crop. This study conducted in north-easternVictoria during 19717–2 led two young CSIRO scientists, J. R. Garratt and G. I. Pearman, encouraged by their Chief, C. H. B. Priestley, to extend micro-environment CO2 studies to larger-scale measurements of CO2 concentration in the background atmosphere. The significant extension of the observation programme required refined measurement techniques to improve both the precision and absolute comparability with observations made by laboratories overseas. Joined in 1974 by P. J. Fraser, they identified the impact of pressure broadening on calibration techniques used in the non-dispersive infrared absorption method of CO2 concentration measurement. This, in turn, led to improved inter-comparability of CO2 concentration data collected around the globe. Acomprehensive aircraft-based air sampling programmewas established in the early 1970s, leading to increased understanding of the time and space variability of CO2 concentration throughout the depth of the troposphere and lower stratosphere in the mid-latitudes of the Southern Hemisphere. In turn this led to: (i) the establishment of a permanent ground-based observatory at Cape Grim, north-western Tasmania; (ii) the development of carbon cycle models; and (iii) measurements of 12CO2, 13CO2 and 14CO2 relative abundances in current and past atmospheres, the last from air samples trapped in ice cores (described in Part 2, the companion paper). The accumulated data from these studies, together with those collected by international colleagues, form the basis of our understanding of the changes of CO2 concentration over thousands of years. In addition, the data have contributed to our understanding of the mechanisms of past and present biogeochemical cycling of CO2 that provides the predictive basis for future changes in CO2 concentration.

中文翻译：

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CSIRO 高精度测量澳大利亚大气 CO2 浓度。第 1 部分：初始动机、技术和飞机采样

大气中的二氧化碳 (CO2) 影响全球地表温度的潜力在 19 世纪中叶首次被认识到。即便如此，由于对化石燃料使用量增加和随之而来的二氧化碳释放到大气中的气候影响的担忧，直到国际地球物理年（1957-8）才开始对大气二氧化碳浓度进行高精度测量。在澳大利亚，对小麦作物光合作用和呼吸作用的研究激发了早期（1960 年代至 70 年代）对 CO2 浓度的高精度测量的兴趣。这项研究于 19717-2 年在维多利亚州东北部进行，由两名年轻的 CSIRO 科学家 JR Garratt 和 GI Pearman 领导，在他们的主管 CHB Priestley 的鼓励下，将微环境 CO2 研究扩展到背景大气中 CO2 浓度的更大规模测量。观测计划的显着扩展需要改进测量技术，以提高与海外实验室观测的精度和绝对可比性。PJ Fraser 于 1974 年加入，他们确定了压力展宽对 CO2 浓度测量的非色散红外吸收方法中使用的校准技术的影响。这反过来又提高了全球收集的 CO2 浓度数据的相互可比性。1970 年代初期建立了全面的基于飞机的空气采样计划，导致对整个南半球中纬度对流层和平流层低层 CO2 浓度的时间和空间变异性的更多了解。反过来，这导致：(i) 在塔斯马尼亚西北部的格里姆角建立了一个永久性的地面观测站；(ii) 碳循环模型的开发；(iii) 对当前和过去大气中 12CO2、13CO2 和 14CO2 相对丰度的测量，最后一次来自冰芯中捕获的空气样本（在第 2 部分，配套文件中描述）。这些研究积累的数据，加上国际同事收集的数据，构成了我们了解数千年来二氧化碳浓度变化的基础。此外，