Trace gas observations for the investigation of mean age and stratospheric transport under the influence of solar variability and long term change

这一提议的目的是通过观测平流层中的年龄示踪剂二氧化碳和SF6，来表征平流层传输时间尺度以及太阳变异性和长期变化对这些时间尺度的影响。两种示踪剂得出的平均年龄之间的差异将被用来研究中间层和平流层之间的耦合。为此，我们建议使用现有的数据集，结合对存档的平流层全空气样本的再分析和使用新的轻型气球载低温全空气采样器进行的观测。这些数据集将涵盖从1973年到现在的一段时间。通过重新分析存档样本，将有可能得出整个时期平均年龄的高质量数据。计划利用这一数据集来描述平流层传输时间尺度及其在太阳变化和长期变化影响下在过去30年中的变化。我们还将研究MIPAS卫星SF6数据用于恢复平均年龄的潜在用途。在与几个建模小组的合作中，我们计划使用这些数据进行模型验证，并使用这些模型来研究太阳变化对平流层动力学和传输时间尺度的影响。我们特别想解决以下问题：-在什么条件下SF6可以用来描述平流层输送时间尺度？-太阳周期是否影响SF6的中间层化学，这是否会导致基于SF6的平均年龄确定出现伪影？-太阳变率是否会影响平流层输送到导致平均年龄变化的程度？-中间层空气被大量输送到极地涡旋的频率是多少？是什么动力过程驱动了这种效应？太阳变化对极地冬季平流层的影响是什么？

The aim of this proposal is to characterize stratospheric transport time scales and the influence of solar variability and long term change on these time scales, using observations of the age tracers CO2 and SF6 in the stratosphere. Differences between mean age derived from both tracers will be used to study the coupling between the mesosphere and the stratosphere. For this purpose we propose to use existing data sets, in combination with reanalyses of archived stratospheric whole air samples and observations performed with a new light weight balloon borne cryogenic whole air sampler. Together these data sets will cover a period starting in 1973 up to the present. By reanalyzing archived samples, it will be possible to derive high quality data of mean age for the entire period. It is planned to use this data set to characterize stratospheric transport time scales and their variability over the last 30 years under the influence of solar variability and long term change. We will also investigate the potential use of MIPAS satellite SF6 data for the retrieval of mean age. In co-operation with several modelling groups we plan to use the data for model validation and to use the models to study the effect of solar variability on stratospheric dynamics and transport time scales. In particular we want to address the following questions:- under which conditions can SF6 be used to characterize stratospheric transport time scales?- does the solar cycle influence the mesospheric chemistry of SF6 and does this lead to an artefact in SF6 based mean age determination?- Does solar variability influence stratospheric transport to the extend that this leads to changes in the mean age?- How often is mesospheric air transported into the polar vortices in significant amounts? Which dynamic process drive this effect and what is the impact of solar variability on the polar winter stratosphere?