气候变化领域集成服务门户(CCPortal): The effect of ice supersaturation and thin cirrus on lapse rates in the upper troposphere

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DOI	10.5194/acp-22-7699-2022
	The effect of ice supersaturation and thin cirrus on lapse rates in the upper troposphere
	Gierens, Klaus; Wilhelm, Lena; Hofer, Sina; Rohs, Susanne
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	7699
结束页码	7712
卷号	22 期号:11 页码:14
英文摘要	In this paper, the effects of ice-supersaturated regions and thin, subvisual cirrus clouds on lapse rates are examined. For that, probability distribution and density functions of the lapse rate and the potential temperature gradients from 10 years of measurement data from the MOZAIC/IAGOS project and ERA5 reanalysis data were produced, and an analysis of an example case of an ice-supersaturated region with a large vertical extent is performed. For the study of the probability distribution and density functions, a distinction is made between ice-subsaturated and ice-supersaturated air masses (persistent contrails) and situations of particularly high ice supersaturation that allow the formation of optically thick and strongly warming contrails. The estimation of the lapse rates involves two adjacent standard pressure levels of the reanalysis surrounding MOZAIC's measurement/flight points. If the upper of these levels is in the stratosphere, the distribution function for subsaturated cases shows much lower lapse rates than those of supersaturated cases. If all levels are in the troposphere, the distributions become more similar, but the average lapse rates are still higher in supersaturated than in subsaturated cases, and the distributions peak at higher values and are narrower in ice-supersaturated regions (ISSRs) than elsewhere. This narrowing is particularly pronounced if there is substantial supersaturation. For the examination of an example case, ERA5 data and forecasts from ICON-EU (DWD) are compared. ERA5 data, in particular, show a large ice-supersaturated region below the tropopause, which was pushed up by uplifting air, while the data of ICON-EU indicate areas of saturation. The lapse rate in this ice-supersaturated region (ISSR), which is large, is associated with clouds and high relative humidity. Supersaturation and cloud formation result from uplifting of air layers. The temperature gradient within an uplifting layer steepens, for both dry and moist air. As soon as condensation or ice formation starts in the upper part of a lifting layer, the release of latent heat begins to decrease the lapse rate, but radiation starts to act in the opposite direction, keeping the lapse rate high. The highest lapse rates close to the stability limit can only be reached in potentially unstable situations.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000810913500001
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/273737
作者单位	Helmholtz Association; German Aerospace Centre (DLR); Helmholtz Association; Research Center Julich; University of Bern; University of Bern
推荐引用方式 GB/T 7714	Gierens, Klaus,Wilhelm, Lena,Hofer, Sina,et al. The effect of ice supersaturation and thin cirrus on lapse rates in the upper troposphere[J],2022,22(11):14.
APA	Gierens, Klaus,Wilhelm, Lena,Hofer, Sina,&Rohs, Susanne.(2022).The effect of ice supersaturation and thin cirrus on lapse rates in the upper troposphere.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(11),14.
MLA	Gierens, Klaus,et al."The effect of ice supersaturation and thin cirrus on lapse rates in the upper troposphere".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.11(2022):14.