气候变化领域集成服务门户(CCPortal): Empirical estimate of the signal content of Holocene temperature proxy records

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DOI	10.5194/cp-15-521-2019
	Empirical estimate of the signal content of Holocene temperature proxy records
	Reschke M.; Rehfeld K.; Laepple T.
发表日期	2019
ISSN	18149324
起始页码	521
结束页码	537
卷号	15 期号:2
英文摘要	Proxy records from climate archives provide evidence about past climate changes, but the recorded signal is affected by non-climate-related effects as well as time uncertainty. As proxy-based climate reconstructions are frequently used to test climate models and to quantitatively infer past climate, we need to improve our understanding of the proxy record signal content as well as the uncertainties involved. In this study, we empirically estimate signal-to-noise ratios (SNRs) of temperature proxy records used in global compilations of the middle to late Holocene (last 6000 years). This is achieved through a comparison of the correlation of proxy time series from nearby sites of three compilations and model time series extracted at the proxy sites from two transient climate model simulations: a Holocene simulation of the ECHAM5/MPI-OM model and the Holocene part of the TraCE-21ka simulation. In all comparisons, we found the mean correlations of the proxy time series on centennial to millennial timescales to be low (R0.2), even for nearby sites, which resulted in low SNR estimates. The estimated SNRs depend on the assumed time uncertainty of the proxy records, the timescale analysed, and the model simulation used. Using the spatial correlation structure of the ECHAM5/MPI-OM simulation, the estimated SNRs on centennial timescales ranged from 0.05-assuming no time uncertainty-to 0.5 for a time uncertainty of 400 years. On millennial timescales, the estimated SNRs were generally higher. Use of the TraCE-21ka correlation structure generally resulted in lower SNR estimates than for ECHAM5/MPI-OM. As the number of available high-resolution proxy records continues to grow, a more detailed analysis of the signal content of specific proxy types should become feasible in the near future. The estimated low signal content of Holocene temperature compilations should caution against over-interpretation of these multi-proxy and multisite syntheses until further studies are able to facilitate a better characterisation of the signal content in paleoclimate records. © 2019 Author(s).
语种	英语
scopus关键词	climate modeling; empirical analysis; estimation method; global climate; Holocene; paleoclimate; proxy climate record
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/146840
作者单位	Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Telegrafenberg A45, Potsdam, 14473, Germany; Institute of Geosciences, University of Potsdam, Karl-Liebknecht-Str. 24/25, Potsdam, 14476, Germany; Institut für Umweltphysik, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 229, Heidelberg, 69120, Germany
推荐引用方式 GB/T 7714	Reschke M.,Rehfeld K.,Laepple T.. Empirical estimate of the signal content of Holocene temperature proxy records[J],2019,15(2).
APA	Reschke M.,Rehfeld K.,&Laepple T..(2019).Empirical estimate of the signal content of Holocene temperature proxy records.Climate of the Past,15(2).
MLA	Reschke M.,et al."Empirical estimate of the signal content of Holocene temperature proxy records".Climate of the Past 15.2(2019).