DOI: 10.5194/cp-10-1093-2014
Scopus记录号: 2-s2.0-84901988551
论文题名: Temperature and precipitation signal in two Alpine ice cores over the period 1961-2001
作者: Mariani I. ; Eichler A. ; Jenk T.M. ; Brönnimann S. ; Auchmann R. ; Leuenberger M.C. ; Schwikowski M.
刊名: Climate of the Past
ISSN: 18149324
出版年: 2014
卷: 10, 期: 3 起始页码: 1093
结束页码: 1108
语种: 英语
Scopus关键词: alpine environment
; annual variation
; anomaly
; ice core
; isotopic ratio
; precipitation (climatology)
; snow accumulation
; stable isotope
; temperature profile
; temporal period
; Europe
; Fiescherhorn Glacier
; Grenz Glacier
; Switzerland
; Valais
英文摘要: Water stable isotope ratios and net snow accumulation in ice cores are commonly interpreted as temperature or precipitation proxies. However, only in a few cases has a direct calibration with instrumental data been attempted. In this study we took advantage of the dense network of observations in the European Alpine region to rigorously test the relationship of the annual and seasonal resolved proxy data from two highly resolved ice cores with local temperature and precipitation. We focused on the time period 1961-2001 with the highest amount and quality of meteorological data and the minimal uncertainty in ice core dating (±1 year). The two ice cores were retrieved from the Fiescherhorn glacier (northern Alps, 3900 m a.s.l.), and Grenzgletscher (southern Alps, 4200 m a.s.l.). A parallel core from the Fiescherhorn glacier allowed assessing the reproducibility of the ice core proxy data. Due to the orographic barrier, the two flanks of the Alpine chain are affected by distinct patterns of precipitation. The different location of the two glaciers therefore offers a unique opportunity to test whether such a specific setting is reflected in the proxy data. On a seasonal scale a high fraction of δ18O variability was explained by the seasonal cycle of temperature (∼60% for the ice cores, ∼70% for the nearby stations of the Global Network of Isotopes in Precipitation - GNIP). When the seasonality is removed, the correlations decrease for all sites, indicating that factors other than temperature such as changing moisture sources and/or precipitation regimes affect the isotopic signal on this timescale. Post-depositional phenomena may additionally modify the ice core data. On an annual scale, the δ18O/temperature relationship was significant at the Fiescherhorn, whereas for Grenzgletscher this was the case only when weighting the temperature with precipitation. In both cases the fraction of interannual temperature variability explained was ∼20%, comparable to the values obtained from the GNIP stations data. Consistently with previous studies, we found an altitude effect for the δ18O of -0.17/100 m for an extended elevation range combining data of the two ice core sites and four GNIP stations. Significant correlations between net accumulation and precipitation were observed for Grenzgletscher during the entire period of investigation, whereas for Fiescherhorn this was the case only for the less recent period (1961-1977). Local phenomena, probably related to wind, seem to partly disturb the Fiescherhorn accumulation record. Spatial correlation analysis shows the two glaciers to be influenced by different precipitation regimes, with the Grenzgletscher reflecting the characteristic precipitation regime south of the Alps and the Fiescherhorn accumulation showing a pattern more closely linked to northern Alpine stations. © 2014 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/49260
Appears in Collections: 气候变化与战略
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Recommended Citation:
Mariani I.,Eichler A.,Jenk T.M.,et al. Temperature and precipitation signal in two Alpine ice cores over the period 1961-2001[J]. Climate of the Past,2014-01-01,10(3)