High accuracy line intensities for carbon dioxide

所有来自地面和太空的二氧化碳遥感活动都依赖于监测二氧化碳如何吸收光。因此，所有这些监测在很大程度上依赖于了解二氧化碳分子的吸收特性，这通常是通过在实验室进行的测量获得的。特别是，准确了解单个吸收谱线的强度对于确定存在多少二氧化碳和解释大气数据至关重要。没有线强度的高精度值，可靠的CO2检索是根本不可能的。特别是由于他们强调二氧化碳浓度随时间的变化，如果要实现既定目标，当前的任务和拟议的任务要求确定的二氧化碳线强度的精度要明显高于1%：强度精确到0.5%以上是真正需要的。在实验室测量的电流线强度根本不能给出这种精度水平：大多数精度约为5%，少数高质量的测量精度可达1 - 3%。因此，目前的cO2回收值受到现有实验室数据的限制。本文的目的是在应用高精度、第一性原理的量子力学强度计算和线位实验数据的基础上，为CO2线强度问题提供一个精确的理论解决方案。由此产生的新的二氧化碳转变强度清单将广泛提供，特别是用于通报用于分子光谱学的大多数大气应用的大气数据库。

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.