气候变化领域集成服务门户(CCPortal): Upper-tropospheric slightly ice-subsaturated regions: frequency of occurrence and statistical evidence for the appearance of contrail cirrus

CCPortal

DOI	10.5194/acp-23-2251-2023
	Upper-tropospheric slightly ice-subsaturated regions: frequency of occurrence and statistical evidence for the appearance of contrail cirrus
	Li, Yun; Mahnke, Christoph; Rohs, Susanne; Bundke, Ulrich; Spelten, Nicole; Dekoutsidis, Georgios; Gross, Silke; Voigt, Christiane; Schumann, Ulrich; Petzold, Andreas; Kraemer, Martina
发表日期	2023
ISSN	1680-7316
EISSN	1680-7324
起始页码	2251
结束页码	2271
卷号	23 期号:3 页码:21
英文摘要	Microphysical, optical, and environmental properties of contrail cirrus and natural cirrus were investigated by applying a new, statistically based contrail-cirrus separation method to 14.7 h of cirrus cloud measurements (sampling frequency 1 Hz, max. similar to 290 m s(-1), total length of sampled in-cloud space similar to 15 000 km) during the airborne campaign ML-CIRRUS in central Europe and the northeast Atlantic flight corridor in spring 2014. We find that pure contrail cirrus appears frequently at the aircraft cruising altitude (CA) range with ambient pressure varying from 200 to 245 hPa. It exhibits a higher median ice particle number concentration (N-ice), a smaller median mass mean radius (R-ice), and lower median ice water content (IWC) (median: Nice=0.045 cm(-3), R-ice=16.6 mu m, IWC = 3.5 ppmv), and it is optically thinner (median extinction coefficient Ext = similar to 0.056 km(-1)) than the cirrus mixture of contrail cirrus, natural in situ-origin and liquid-origin cirrus found around the CA range (median: N-ice=0.038 cm(-3), R-ice=24.1 mu m, IWC = 8.3 ppmv, Ext =similar to 0.096 km(-1)). The lowest and thickest cirrus, consisting of a few large ice particles, are identified as pure natural liquid-origin cirrus (median: N-ice=0.018 cm(-3), R-ice=42.4 mu m, IWC = 21.7 ppmv, Ext = similar to 0.137 km(-1)). Furthermore, we observe that, in particular, contrail cirrus occurs more often in slightly ice-subsaturated instead of merely ice-saturated to supersaturated air as often assumed, thus indicating the possibility of enlarged contrail cirrus existence regions. The enlargement is estimated, based on IAGOS long-term observations of relative humidity with respect to ice (RHice) aboard passenger aircraft, to be approximately 10 % for Europe and the North Atlantic region, with the RHice threshold for contrail cirrus existence decreased from 100 % to 90 % RHice and a 4 h lifetime of contrail cirrus in slight ice subsaturation assumed. This increase may not only lead to a non-negligible change in contrail cirrus coverage and radiative forcing, but also affect the mitigation strategies of reducing contrails by rerouting flights.
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:000938012500001
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/273380
作者单位	Helmholtz Association; Research Center Julich; Helmholtz Association; Research Center Julich; Helmholtz Association; German Aerospace Centre (DLR); Johannes Gutenberg University of Mainz
推荐引用方式 GB/T 7714	Li, Yun,Mahnke, Christoph,Rohs, Susanne,et al. Upper-tropospheric slightly ice-subsaturated regions: frequency of occurrence and statistical evidence for the appearance of contrail cirrus[J],2023,23(3):21.
APA	Li, Yun.,Mahnke, Christoph.,Rohs, Susanne.,Bundke, Ulrich.,Spelten, Nicole.,...&Kraemer, Martina.(2023).Upper-tropospheric slightly ice-subsaturated regions: frequency of occurrence and statistical evidence for the appearance of contrail cirrus.ATMOSPHERIC CHEMISTRY AND PHYSICS,23(3),21.
MLA	Li, Yun,et al."Upper-tropospheric slightly ice-subsaturated regions: frequency of occurrence and statistical evidence for the appearance of contrail cirrus".ATMOSPHERIC CHEMISTRY AND PHYSICS 23.3(2023):21.