Department of Chemistry and Biochemistry, James Madison University, MSC 4501, Harrisonburg, Virginia 22807, USA.
J Phys Chem A. 2011 Dec 1;115(47):13804-10. doi: 10.1021/jp208800s. Epub 2011 Nov 4.
Remote sensing of CO(2) requires high-fidelity reference data of spectral line parameters to be successful. The 6360 cm(-1) region is commonly used by satellites, field campaigns, and point-source gas sensors because it contains well-characterized and relatively isolated transitions of appropriate line strengths for atmospheric applications. However, the presence of gases other than CO(2), N(2), and O(2) can be a source of uncertainty for atmospheric measurements. Near 6360 cm(-1), there are numerous H(2)O and HDO transitions. Water makes up approximately 1-4% of Earth's lower atmosphere and can interfere with remote sensing measurements by (1) appearing as a direct spectral interference or (2) acting as a foreign broadener for CO(2) lines. The primary goal of this work was to quantify H(2)O broadening of CO(2) through precision spectroscopy measurements on the R16e transition at 6359.967 cm(-1) and its two nearest neighbors. A secondary goal was to assess the accuracy of H(2)O reference line parameters in the HITRAN 2008 database for spectrally removing typical levels of moisture from air samples containing approximately 400 ppm of CO(2).
二氧化碳的遥感需要具有高保真度的谱线参数参考数据才能成功。6360cm-1 区域通常被卫星、现场观测和点源气体传感器使用，因为它包含了特征良好且相对独立的跃迁，这些跃迁具有适合大气应用的适当线强度。然而，除了 CO2、N2 和 O2 之外的气体的存在可能会给大气测量带来不确定性。在 6360cm-1 附近，有许多 H2O 和 HDO 跃迁。水约占地球低层大气的 1-4%，可以通过以下两种方式干扰遥感测量：(1) 直接出现光谱干扰，或 (2) 作为 CO2 线的外来展宽剂。这项工作的主要目标是通过对 6359.967cm-1 处的 R16e 跃迁及其两个最近邻进行精密光谱测量，量化 H2O 对 CO2 的展宽。次要目标是评估 HITRAN 2008 数据库中 H2O 参考线参数的准确性，以从含有约 400ppm CO2 的空气样本中去除典型水平的水分。
