当前位置: X-MOL 学术Nat. Geosci. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
The strength of the meridional overturning circulation of the stratosphere
Nature Geoscience ( IF 18.3 ) Pub Date : 2017-08-28 , DOI: 10.1038/ngeo3013
Marianna Linz 1 , R Alan Plumb 2 , Edwin P Gerber 3 , Florian J Haenel 4 , Gabriele Stiller 4 , Douglas E Kinnison 5 , Alison Ming 6 , Jessica L Neu 7
Affiliation  

The distribution of gases such as ozone and water vapour in the stratosphere—which affect surface climate—is influenced by the meridional overturning of mass in the stratosphere, the Brewer–Dobson circulation. However, observation-based estimates of the global strength of this circulation are difficult to obtain. Here we present two calculations of the mean strength of the meridional overturning of the stratosphere. We analyse satellite data that document the global diabatic circulation between 2007–2011, and compare these to three reanalysis data sets and to simulations with a state-of-the-art chemistry–climate model. Using measurements of sulfur hexafluoride (SF6) and nitrous oxide, we calculate the global mean diabatic overturning mass flux throughout the stratosphere. In the lower stratosphere, these two estimates agree, and at a potential temperature level of 460 K (about 20 km or 60 hPa in tropics) the global circulation strength is 6.3–7.6 × 109 kg s−1. Higher in the atmosphere, only the SF6-based estimate is available, and it diverges from the reanalysis data and simulations. Interpretation of the SF6-data-based estimate is limited because of a mesospheric sink of SF6; however, the reanalyses also differ substantially from each other. We conclude that the uncertainty in the mean meridional overturning circulation strength at upper levels of the stratosphere amounts to at least 100%.



中文翻译:

平流层经向翻转环流强度

平流层中臭氧和水蒸气等气体的分布——影响地表气候——受到平流层中质量的经向翻转,即布鲁尔-多布森环流的影响。然而,很难获得对这种环流全球强度的基于观测的估计。在这里,我们提出了平流层经向翻转的平均强度的两种计算。我们分析了记录 2007 年至 2011 年间全球非绝热环流的卫星数据,并将这些数据与三个再分析数据集以及使用最先进的化学气候模型进行的模拟进行了比较。使用六氟化硫 (SF 6)和一氧化二氮,我们计算了整个平流层的全球平均非绝热倾覆质量通量。在平流层较低层,这两个估计一致,在潜在温度水平为 460 K(热带地区约为 20 km 或 60 hPa)时,全球环流强度为 6.3–7.6 × 10 9  kg s -1。在大气层的更高处,只有基于 SF 6的估计可用,并且它与再分析数据和模拟不同。由于 SF 6 的中层汇,对基于数据的估计的解释有限的 SF 6; 然而,重新分析彼此之间也存在很大差异。我们得出结论,平流层高层的平均经向翻转环流强度的不确定性至少达到 100%。

更新日期:2017-09-05
down
wechat
bug