High accuracy line intensities for carbon dioxide

所有的二氧化碳遥感活动，无论是从地面还是太空，都依赖于监测二氧化碳如何吸收光线。因此，所有这些监测在很大程度上依赖于对二氧化碳分子吸收性质的了解，而二氧化碳分子的吸收性质通常是通过在实验室进行测量获得的。特别是，对个别吸收线强度的准确了解对于确定存在多少二氧化碳和解释大气数据是至关重要的。如果没有高精度的谱线强度值，可靠的二氧化碳反演是不可能的。特别是由于它们强调二氧化碳浓度随时间的变化，当前的飞行任务和拟议的飞行任务要求，如果要实现其宣称的目标，二氧化碳谱线强度的测定精度必须大大高于1%：确实需要准确到优于0.5%的浓度。在实验室中测量的电流线强度根本不能提供这种水平的精度：大多数精度在5%左右，少数高质量测量的精度在1-3%之间。因此，目前的二氧化碳反演值受到现有实验室数据的限制。这一提议的目的是基于高精度的第一性原理强度量子力学计算和谱线位置的实验数据，为CO2谱线强度问题提供准确的理论解决方案。由此产生的二氧化碳转变强度的新清单将被广泛使用，特别是用于为用于分子光谱学的大多数大气应用的大气数据库提供信息。

All CO2 remote sensing activity, from both the ground and space, relies on monitoring how CO2 absorbs light. All this monitoring is therefore heavily dependent on understanding the absorption properties of the CO2 molecule which is usually obtained by measurements performed in the laboratory. In particular the accurate knowledge of the strength of individual absorption lines is crucial to determining how much CO2 is present and allowing the atmospheric data to be interpreted. Without high accuracy values for line intensities, reliable CO2 retrievals are simply not possible. Particularly with their emphasis on variation of CO2 concentrations with time, current missions and proposed missions require CO2 line intensities to be determined to significantly better than 1% accuracy if they are to fulfill their stated goals: intensities accurate to better than 0.5% are really required. Current line intensities measured in the laboratory simply do not gives this level of accuracy: most are accurate to about 5% with a few high quality measurements being good to 1 - 3%. Hence current cO2 retrievals values are limited by the available laboratory data. The aim of this proposal is to provide an accurate theoretical solution to the problem of CO2 line intensities based on the application of high accuracy, first principles quantum mechanical calculations for the intensities and experimental data for the line positions. The resulting new lists of CO2 transition intensities will be made widely available and, in particular, used to inform atmospheric databases which are used for the majority of atmospheric applications of molecular spectroscopy.