Examining the extra-tropical upper troposphere and lower stratosphere using remote sensing limb-sounder measurements of unprecedented vertical resolution

对流层和平流层之间的微量气体交换极大地促进了对流层上层和下层（UTLS）成分的变化和变率，这是地面气候变化的主要驱动因素。这表明需要对UTLS中的流程进行更好的定量理解。研究飞机的红外肢体探测可以提供多种微量气体的二维截面。传统的翼缘探测仪无法沿其视线分辨观测到的气团，与之相反，新的GLORIA（大气辐射成像Gimballed limb Observer for Radiance Imaging of Atmosphere）仪器能够对痕量气体分布进行三维重建。除其他事项外，这将提供混合过程的高分辨率快照，而不是可以增强我们对其的定量理解。拟议的工作将使用GLORIA测量来重建示踪剂，这是对流层和平流层空气的最佳特征。首先，需要确定最佳的可检索示踪剂。在第二步中，检索过程所施加的失真将尽可能地减少。最后，推导出的示踪剂将用于分析副热带急流附近的化学对流层顶和水平混合。

Trace gas exchange between troposphere and stratosphere greatly contributes to upper troposphere and lower stratosphere (UTLS) composition changes and variability, which are major drivers of surface climate change. This points to the need of a better quantitative understanding of processes in the UTLS. Infrared limb sounding from research aircrafts can provide 2-D cross-sections of multiple trace gas species. In contrast to conventional limb sounders, which are unable to resolve the observed airmass along their line-of-sight, the new GLORIA (Gimballed Limb Observer for Radiance Imaging of the Atmosphere) instrument enables the 3-D reconstruction of trace gas distributions. This will, among other things, provide highly resolved snapshots of mixing processes than can enhance our quantitative understanding thereof.The proposed work will use GLORIA measurements to reconstruct tracers, which best characterise tropospheric and stratospheric air. First, the best retrievable tracers need to be identified. In a second step the distortion imposed by the retrieval process will be reduced as much a possible. Finally, the derived tracers will be used to analyse the chemical tropopause and horizontal mixing in the vicinity of the sub-tropical jet.