气候变化领域集成服务门户(CCPortal): Climatic information archived in ice cores: Impact of intermittency and diffusion on the recorded isotopic signal in Antarctica

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DOI	10.5194/cp-16-1581-2020
	Climatic information archived in ice cores: Impact of intermittency and diffusion on the recorded isotopic signal in Antarctica
	Casado M.; Münch T.; Laepple T.
发表日期	2020
ISSN	18149324
起始页码	1581
结束页码	1598
卷号	16 期号:4
英文摘要	The isotopic signal (δ18O and dD) imprinted in ice cores from Antarctica is not solely generated by the temperature sensitivity of the isotopic composition of precipitation, but it also contains the signature of the intermittency of the precipitation patterns, as well as of post-deposition processes occurring at the surface and in the firn. This leads to a proxy signal recorded by the ice cores that may not be representative of the local climate variations. Due to precipitation intermittency, the ice cores only record brief snapshots of the climatic conditions, resulting in aliasing of the climatic signal and thus a large amount of noise which reduces the minimum temporal resolution at which a meaningful signal can be retrieved. The analyses are further complicated by isotopic diffusion, which acts as a low-pass filter that dampens any high-frequency changes. Here, we use reanalysis data (ERAInterim) combined with satellite products of accumulation to evaluate the spatial distribution of the numerical estimates of the transfer function that describes the formation of the isotopic signal across Antarctica. As a result, the minimum timescales at which the signal-to-noise ratio exceeds unity range from less than 1 year at the coast to about 1000 years further inland. Based on solely physical processes, we are thus able to define a lower bound for the timescales at which climate variability can be reconstructed from the isotopic composition in ice cores. © 2020 Author(s).
语种	英语
scopus关键词	diffusion; ice core; isotopic composition; precipitation (climatology); proxy climate record; signal-to-noise ratio; spatial distribution; temperature; transfer function; Antarctica
来源期刊	Climate of the Past
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146678
作者单位	Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung, Research Unit Potsdam, Telegrafenberg A45, Potsdam, 14473, Germany; MARUM-Center for Marine Environmental Sciences and Faculty of Geosciences, University of Bremen, Bremen, 28334, Germany
推荐引用方式 GB/T 7714	Casado M.,Münch T.,Laepple T.. Climatic information archived in ice cores: Impact of intermittency and diffusion on the recorded isotopic signal in Antarctica[J],2020,16(4).
APA	Casado M.,Münch T.,&Laepple T..(2020).Climatic information archived in ice cores: Impact of intermittency and diffusion on the recorded isotopic signal in Antarctica.Climate of the Past,16(4).
MLA	Casado M.,et al."Climatic information archived in ice cores: Impact of intermittency and diffusion on the recorded isotopic signal in Antarctica".Climate of the Past 16.4(2020).