气候变化领域集成服务门户(CCPortal): Very old firn air linked to strong density layering at Styx Glacier, coastal Victoria Land, East Antarctica

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DOI	10.5194/tc-13-2407-2019
	Very old firn air linked to strong density layering at Styx Glacier, coastal Victoria Land, East Antarctica
	Jang Y.; Bum Hong S.; Buizert C.; Lee H.-G.; Han S.-Y.; Yang J.-W.; Iizuka Y.; Hori A.; Han Y.; Joon Jun S.; Tans P.; Choi T.; Kim S.-J.; Do Hur S.; Ahn J.
发表日期	2019
ISSN	19940416
EISSN	13
起始页码	2407
结束页码	2419
卷号	13 期号:9
英文摘要	Firn air provides plenty of old air from the near past, and can therefore be useful for understanding human impact on the recent history of the atmospheric composition. Most of the existing firn air records cover only the last several decades (typically 40 to 55 years) and are insufficient to understand the early part of anthropogenic impacts on the atmosphere. In contrast, a few firn air records from inland sites, where temperatures and snow accumulation rates are very low, go back in time about a century. In this study, we report an unusually old firn air effective CO2 age of 93 years from Styx Glacier, near the Ross Sea coast in Antarctica. This is the first report of such an old firn air age (> 55 years) from a warm coastal site. The lock-in zone thickness of 12.4m is larger than at other sites where snow accumulation rates and air temperature are similar. High-resolution X-ray density measurements demonstrate a high variability of the vertical snow density at Styx Glacier. The CH4 mole fraction and total air content of the closed pores also indicate large variations in centimeter-scale depth intervals, indicative of layering. We hypothesize that the large density variations in the firn increase the thickness of the lock-in zone and, consequently, increase the firn air ages because the age of firn air increases more rapidly with depth in the lock-in zone than in the diffusive zone. Our study demonstrates that all else being equal, sites where weather conditions are favorable for the formation of large density variations at the lock-in zone preserve older air within their open porosity, making them ideal places for firn air sampling. © 2019 American Society of Mechanical Engineers (ASME). All rights reserved.
学科领域	anthropogenic effect; carbon dioxide; diffusivity; glacier; porosity; weather; Antarctica; East Antarctica; Ross Sea; Southern Ocean; Victoria Land; Styx
语种	英语
scopus关键词	anthropogenic effect; carbon dioxide; diffusivity; glacier; porosity; weather; Antarctica; East Antarctica; Ross Sea; Southern Ocean; Victoria Land; Styx
来源期刊	The Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/118837
作者单位	School of Earth and Environmental Sciences, Seoul National University, Seoul, South Korea; Korea Polar Research Institute, Incheon, South Korea; College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, United States; Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan; Kitami Institute of Technology, Kitami, Japan; National Oceanic and Atmospheric Administration, Earth System Research Laboratory, Boulder, CO, United States
推荐引用方式 GB/T 7714	Jang Y.,Bum Hong S.,Buizert C.,et al. Very old firn air linked to strong density layering at Styx Glacier, coastal Victoria Land, East Antarctica[J],2019,13(9).
APA	Jang Y..,Bum Hong S..,Buizert C..,Lee H.-G..,Han S.-Y..,...&Ahn J..(2019).Very old firn air linked to strong density layering at Styx Glacier, coastal Victoria Land, East Antarctica.The Cryosphere,13(9).
MLA	Jang Y.,et al."Very old firn air linked to strong density layering at Styx Glacier, coastal Victoria Land, East Antarctica".The Cryosphere 13.9(2019).