气候变化领域集成服务门户(CCPortal): Archival processes of the water stable isotope signal in East Antarctic ice cores

CCPortal

DOI	10.5194/tc-12-1745-2018
	Archival processes of the water stable isotope signal in East Antarctic ice cores
	Casado M.; Landais A.; Picard G.; Münch T.; Laepple T.; Stenni B.; Dreossi G.; Ekaykin A.; Arnaud L.; Genthon C.; Touzeau A.; Masson-Delmotte V.; Jouzel J.
发表日期	2018
ISSN	19940416
卷号	12 期号:5
英文摘要	The oldest ice core records are obtained from the East Antarctic Plateau. Water isotopes are key proxies to reconstructing past climatic conditions over the ice sheet and at the evaporation source. The accuracy of climate reconstructions depends on knowledge of all processes affecting water vapour, precipitation and snow isotopic compositions. Fractionation processes are well understood and can be integrated in trajectory-based Rayleigh distillation and isotope-enabled climate models. However, a quantitative understanding of processes potentially altering snow isotopic composition after deposition is still missing. In low-accumulation sites, such as those found in East Antarctica, these poorly constrained processes are likely to play a significant role and limit the interpretability of an ice core's isotopic composition. By combining observations of isotopic composition in vapour, precipitation, surface snow and buried snow from Dome C, a deep ice core site on the East Antarctic Plateau, we found indications of a seasonal impact of metamorphism on the surface snow isotopic signal when compared to the initial precipitation. Particularly in summer, exchanges of water molecules between vapour and snow are driven by the diurnal sublimation-condensation cycles. Overall, we observe in between precipitation events modification of the surface snow isotopic composition. Using high-resolution water isotopic composition profiles from snow pits at five Antarctic sites with different accumulation rates, we identified common patterns which cannot be attributed to the seasonal variability of precipitation. These differences in the precipitation, surface snow and buried snow isotopic composition provide evidence of post-deposition processes affecting ice core records in low-accumulation areas. © 2018 Author(s).
学科领域	accuracy assessment; climate modeling; climate signal; historical record; ice core; ice sheet; isotopic composition; isotopic fractionation; metamorphism; paleoclimate; reconstruction; seasonal variation; snow accumulation; stable isotope; sublimation; Antarctic Plateau; Antarctica; Dome Concordia; East Antarctica
语种	英语
scopus关键词	accuracy assessment; climate modeling; climate signal; historical record; ice core; ice sheet; isotopic composition; isotopic fractionation; metamorphism; paleoclimate; reconstruction; seasonal variation; snow accumulation; stable isotope; sublimation; Antarctic Plateau; Antarctica; Dome Concordia; East Antarctica
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119145
作者单位	Laboratoire des Sciences du Climat et de l'Environnement - IPSL, UMR 8212, CEA-CNRS-UVSQ-UPS, Gif-sur-Yvette, France; Université Grenoble Alpes, CNRS, LIPHY, Grenoble, 38000, France; Université Grenoble Alpes, CNRS, LGGE, Grenoble, 38400, France; Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Telegrafenberg A43, Potsdam, 14473, Germany; Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24/25, Potsdam, 14476, Germany; DAIS, Ca'Foscari University of Venice, Venice, Italy; Arctic and Antarctic Research Institute, St.-Petersburg, Russian Federation; Institute of Earth Sciences, St. Petersburg State University, Russian Federation
推荐引用方式 GB/T 7714	Casado M.,Landais A.,Picard G.,et al. Archival processes of the water stable isotope signal in East Antarctic ice cores[J],2018,12(5).
APA	Casado M..,Landais A..,Picard G..,Münch T..,Laepple T..,...&Jouzel J..(2018).Archival processes of the water stable isotope signal in East Antarctic ice cores.Cryosphere,12(5).
MLA	Casado M.,et al."Archival processes of the water stable isotope signal in East Antarctic ice cores".Cryosphere 12.5(2018).