An ice core paleoclimate study of Windy Dome, Franz Josef Land (Russia)
- 出版日期：2002.
- 页数：218 p. :
- 第一责任说明：Keith Allen Henderson.
- 分类号：a515.2 ; a517 ; a133
- ISBN：0493747923(ebk.) :
MARC全文
02h0025398 20110920110007.0 cr un||||||||| 110920s2002 xx ||||f|||d||||||||eng | AAI3059259 0493747923(ebk.) : CNY371.35 NGL NGL NGL a515.2 ; a517 ; a133 Henderson, Keith Allen. An ice core paleoclimate study of Windy Dome, Franz Josef Land (Russia) [electronic resource] : development of a recent climate history for the Barents Sea / Keith Allen Henderson. 2002. 218 p. : digital, PDF file. Source: Dissertation Abstracts International, Volume: 63-07, Section: B, page: 3197. ; Adviser: Lonnie G. Thompson. Thesis (Ph.D.) -- The Ohio State University, 2002. A 315-meter ice core obtained in April-May, 1997 from the summit of Windy Dome, Franz Josef Land in the Russian high Arctic (81°N, 64°E, 509 masl) reflects 772 years of climate variability in the Barents Sea region. Paleotemperatures inferred from oxygen isotope (δ18O) calibration indicate a dramatic and sustained wintertime warming of more than 8°C occurring abruptly around 1910, halting the persistent cold temperatures of the Little Ice Age (LIA, -1450 to -1870 A.D.). Summer temperatures, related to meltwater formation, rose earlier (-1850) but only by approximately 0.5°C relative to the LIA mean, consistent with regional tree-ring histories.;The age scale for the finely-sampled Windy Dome ice core was generated by three-parameter (chloride, δ18O, and melt-stratigraphy) reconciled layer counting, guided by the detection of recent nuclear testing horizons and nine known volcanic eruptions, and confirmed by duplicating the cosmogenic record of solar variability. Accordingly, a proposed common time scale based on this superior chronology is presented, that realigns previous Eurasian Arctic ice core records to illustrate a consistent pattern of climate change along the northern Barents continental margin from Nordauslandet, Svalbard to Severnaya Zemlya. While the temporal climate changes fit a global paradigm, it is cautioned that the wintertime fluctuations that occurred here represent a threshold change in the position of the polar front and should be weighted accordingly when considering hemispheric-scale climatology.;Soluble ionic constituents in the ice core reveal a strong signature of anthropogenic emissions by rising sulfate and nitrate levels, and also 20th century agricultural activity via ammonium. The degree of post-depositional modification of core parameters was quantified, with ion fractionation and multi-year percolation indicated to reduce concentrations of more mobile ions (e.g., SO42-, Mg2+) by up to 10–15%, and solid-liquid stable isotope fractionation currently responsible for a -0.9‰ difference between bubbly and melt-infiltrated ice. Regular oscillations in pH values suggest a succession of “stacked percolation cells” that are sealed and archived every 13–14 years on average. Periodicities of 40–70 years were detected by Singular-Spectrum Analysis (SSA) in several parameters, and the annual signal strength of δ 18O and chloride is shown to be related to the extent of meltwater formation and thereby summer temperatures. Glaciers ; Climatic changes ; Paleoclimatology. Russia ; Franz Josef Land. ; Barents Sea. Electronic books. aeBook. aCN bNGL http://proquest.calis.edu.cn/umi/detail_usmark.jsp?searchword=pub_number%3DAAI3059259&singlesearch=no&channelid=%CF%B8%C0%C0&record=1 NGL Bs930 rCNY371.35 ; h1 bs1107