In-situ measurements of chemically and radiatively important atmospheric gases from the Advanced Global Atmospheric Gas Experiment (AGAGE) and affiliated stations.

In the ALE/GAGE/AGAGE global network program, continuous high frequency gas chromatographic measurements of four biogenic/anthropogenic gases (methane, CH4; nitrous oxide, N2O; hydrogen, H2; and carbon monoxide, CO) and several anthropogenic gases that contribute to stratospheric ozone destruction and/or to the greenhouse effect have been carried out at five globally distributed sites for several years. The program, which began in 1978, is divided into three parts associated with three changes in instrumentation: the Atmospheric Lifetime Experiment (ALE), which used Hewlett Packard HP5840 gas chromatographs; the Global Atmospheric Gases Experiment (GAGE), which used HP5880 gas chromatographs; and the present Advanced GAGE (AGAGE). AGAGE uses two types of instruments: a gas chromatograph with multiple detectors (GC-MD), and a gas chromatograph with mass spectrometric analysis (GC-MS). Beginning in January 2004, an improved cryogenic preconcentration system (Medusa) replaced the absorption-desorption module in the GC-MS systems at Mace Head and Cape Grim; this provided improved capability to measure a broader range of volatile perfluorocarbons with high global warming potentials. The Medusa GC-MS systems were subsequently used at other AGAGE stations (Trinidad Head, Barbados, American Samoa, Zeppelin, Jungfraujoch, and Goan) after the initial setup at Mace Head and Cape Grim. More information may be found at the AGAGE home page: https://agage.mit.edu/instruments.Compared to the previous version (https://data.ess-dive.lbl.gov/view/doi:10.3334/CDIAC/ATG.DB1001), the latest update (Agage_gcmd_gcms_data_2021_04_07_tar.gz) includes 6 months of new data through the end of March 2020. Two new compounds, HCFC-132b, and HCFC-133a, are also included in this version. For a complete list of released compounds and used standard scales, please see “AGAGE_scale_2021_v1.pdf” file. Additional information can also be found on the AGAGE website (https://agage.mit.edu).

在ALE/GAGE/AGAGE全球大气观测网络计划中，研究团队多年来在全球5个分布式观测站点，针对4种生物/人为源气体（甲烷CH₄、一氧化二氮N₂O、氢气H₂、一氧化碳CO）以及若干会破坏平流层臭氧和/或加剧温室效应的人为源气体，开展了连续高频气相色谱监测。该计划始于1978年，依据仪器系统的三次迭代升级分为三个阶段：采用惠普（Hewlett Packard）HP5840气相色谱仪的大气寿命实验（Atmospheric Lifetime Experiment, ALE）、采用惠普HP5880气相色谱仪的全球大气气体实验（Global Atmospheric Gases Experiment, GAGE），以及当前的先进全球大气气体实验（Advanced GAGE, AGAGE）。AGAGE搭载两类观测仪器：带多检测器的气相色谱仪（gas chromatograph with multiple detectors, GC-MD）与气相色谱-质谱联用仪（gas chromatograph with mass spectrometric analysis, GC-MS）。2004年1月起，位于梅斯黑德（Mace Head）与格雷姆角（Cape Grim）的GC-MS系统中，改进型低温预浓缩系统（Medusa）取代了原有的吸收-解吸模块，此举显著提升了对一系列具有较高全球增温潜势的全氟化挥发性碳化物的宽量程测量能力。在梅斯黑德和格雷姆角完成初始部署后，Medusa GC-MS系统后续被推广应用于其余AGAGE观测站点，包括特里尼达德角（Trinidad Head）、巴巴多斯（Barbados）、美属萨摩亚（American Samoa）、齐柏林（Zeppelin）、少女峰（Jungfraujoch）以及果阿（Goan）站点。更多相关细节可查阅AGAGE官方仪器页面：https://agage.mit.edu/instruments。相较于旧版数据集（https://data.ess-dive.lbl.gov/view/doi:10.3334/CDIAC/ATG.DB1001），本次最新更新包（Agage_gcmd_gcms_data_2021_04_07_tar.gz）新增了截至2020年3月的6个月观测数据，同时补充了HCFC-132b与HCFC-133a两种新化合物。如需获取完整的已发布化合物列表与所用标准量表，请查阅"AGAGE_scale_2021_v1.pdf"文件。其他补充信息亦可访问AGAGE官方网站（https://agage.mit.edu）获取。