<> "The repository administrator has not yet configured an RDF license."^^ . <> . . "Potentials and limitations of multi-proxy records in speleothem research - Case studies in complex climate systems"^^ . "The central goal of this dissertation is assessing the benefits and limitations of multi-proxy approaches in speleothem research with respect to paleo climate reconstruction. Hence, the aims were evaluating the environmental controls of speleothem proxies such as stable isotopes or trace elements, and the application to samples from locations affected by complex climate interactions. Thus, this thesis provides an important contribution to the recent scientific discussion in speleothem and climate research.\r\nThe presented case studies comprise a Holocene stalagmite from southwestern Romania, and two speleothems from the Caribbean realm covering major parts of the last Glacial cycle. All records are based on high-precision dating methods, such as 230Th/U dating, lamina counting or radiocarbon dating. The analysis of stable isotope δ18O and δ13C composition together with trace elemental signatures enables a broad survey of past environmental changes comprising temperature and rainfall variability as well as soil and vegetation dynamics. The studies presented in this thesis demonstrate the strong benefits of the combination of several proxies in speleothems and in the investigated regions, they provide the first \r\nspeleothem derived climate reconstructions, respectively, combining successfully both stable isotopes and elemental proxies.\r\nIn tropical locations, the δ18O values in speleothems may be reliable recorders of past rainfall changes. However, a number of processes such as temperature variability, source effects and disequilibrium fractionation affecting the oxygen isotopic composition have to be carefully evaluated. Under certain circumstances, trace elements such as magnesium and strontium are found to constitute valuable tracers of hydrological variability, whereas phosphorus is most commonly associated with soil and vegetation dynamics. However, the interpretation\r\nof P/Ca is found to be diverse in the three case studies. To explain the non-conventional P systematics in the Cuban sample, a mechanism was devised which previously has received little attention. Stalagmite C09-2 from southwestern Romania emerged as one of the unique samples appropriate for quantitative reconstruction of past climate variability. The Mg/Ca ratio was found to be strongly connected with past winter rainfall, and the reconstructed precipitation estimates for the last 3.6 ka are in agreement with other local and supra-regional records. The δ18O record from stalagmite PR-LA-1 is one of the first speleothem derived long-term reconstructions\r\nof rainfall variability from the western tropical \r\n Atlantic realm which demonstrates the imprint of both the Heinrich stadials as well as the Dansgaard/Oeschger cycles on Puerto Rico during the last Glacial. In \r\naddition, stalagmite CM from western Cuba provides one of\r\nthe longest speleothem records from the Caribbean region, and the geochemical evidence from the stable isotope and trace element signatures gives a comprehensive picture of past environmental variability over a long time interval of the last Glacial."^^ . "2017" . . . . . . . "Sophie Friederike"^^ . "Warken, geb. Winterhalder"^^ . "Sophie Friederike Warken, geb. Winterhalder"^^ . . . . . . "Potentials and limitations of multi-proxy records in speleothem research - Case studies in complex climate systems (PDF)"^^ . . . "PhDthesis_Warken_2017.pdf"^^ . . . "Potentials and limitations of multi-proxy records in speleothem research - Case studies in complex climate systems (Other)"^^ . . . . . . "indexcodes.txt"^^ . . . "Potentials and limitations of multi-proxy records in speleothem research - Case studies in complex climate systems (Other)"^^ . . . . . . "lightbox.jpg"^^ . . . "Potentials and limitations of multi-proxy records in speleothem research - Case studies in complex climate systems (Other)"^^ . . . . . . "preview.jpg"^^ . . . "Potentials and limitations of multi-proxy records in speleothem research - Case studies in complex climate systems (Other)"^^ . . . . . . "medium.jpg"^^ . . . "Potentials and limitations of multi-proxy records in speleothem research - Case studies in complex climate systems (Other)"^^ . . . . . . "small.jpg"^^ . . "HTML Summary of #22921 \n\nPotentials and limitations of multi-proxy records in speleothem research - Case studies in complex climate systems\n\n" . "text/html" . . . "530 Physik"@de . "530 Physics"@en . . . "550 Geowissenschaften"@de . "550 Earth sciences"@en . .