TY - JOUR A1 - Warken, Sophie Friederike A1 - Fohlmeister, Jens Bernd A1 - Schröder-Ritzrauh, Andrea A1 - Constantin, Silviu A1 - Spötl, Christoph A1 - Gerdes, Axel A1 - Esper, Jan A1 - Frank, Norbert A1 - Arps, Jennifer A1 - Terente, Mihai A1 - Riechelmann, Dana Felicitas Christine A1 - Mangini, Augusto A1 - Scholz, Denis T1 - Reconstruction of late Holocene autumn/winter precipitation variability in SW Romania from a high-resolution speleothem trace element record JF - Earth & planetary science letters N2 - We present the first high-resolution trace element (Mg/Ca, Sr/Ca, Ba/Ca) record from a stalagmite in southwestern Romania covering the last 3.6 ka, which provides the potential for quantitative climate reconstruction. Precise age control is based on three independent dating methods, in particular for the last 250 yr, where chemical lamina counting is combined with the identification of the 20th century radiocarbon bomb peak and Th-230/U dating. Long-term cave monitoring and model simulations of drip water and speleothem elemental variability indicate that precipitation-related processes are the main drivers of speleothem Mg/Ca ratios. Calibration against instrumental climate data shows a significant anti-correlation of speleothem Mg/Ca ratios with autumn/winter (October to March) precipitation (r = -0.61, p < 0.01), which is statistically robust when considering age uncertainties and auto-correlation. This relationship is used to develop a quantitative reconstruction of autumn/winter precipitation. During the late Holocene, our data suggest a heterogeneous pattern of past regional winter hydroclimate in the Carpathian/Balkan realm, along with intermittent weakening of the dominant influence of North Atlantic forcing. In agreement with other regional paleo-hydrological reconstructions, the observed variability reveals periodically occurring strong NW-SE hydro-climate gradients. We hypothesize, that this pattern is caused by shifts of the eastern edge of the area of influence of the NAO across central eastern Europe due to the confluence of North Atlantic forcing, and other climatic features such as the East Atlantic/Western Russia (EAWR) pattern. (C) 2018 Elsevier B.V. All rights reserved. KW - speleothem KW - trace elements KW - proxy calibration KW - precipitation reconstruction KW - Romania KW - North Atlantic forcing Y1 - 2018 U6 - https://doi.org/10.1016/j.epsl.2018.07.027 SN - 0012-821X SN - 1385-013X VL - 499 SP - 122 EP - 133 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Comas-Bru, Laia A1 - Harrison, Sandy P. A1 - Werner, Martin A1 - Rehfeld, Kira A1 - Scroxton, Nick A1 - Veiga-Pires, Cristina A1 - Ahmad, Syed Masood A1 - Brahim, Yassine Ait A1 - Mozhdehi, Sahar Amirnezhad A1 - Arienzo, Monica A1 - Atsawawaranunt, Kamolphat A1 - Baker, Andy A1 - Braun, Kerstin A1 - Breitenbach, Sebastian Franz Martin A1 - Burstyn, Yuval A1 - Chawchai, Sakonvan A1 - Columbu, Andrea A1 - Deininger, Michael A1 - Demeny, Attila A1 - Dixon, Bronwyn A1 - Hatvani, Istvan Gabor A1 - Hu, Jun A1 - Kaushal, Nikita A1 - Kern, Zoltan A1 - Labuhn, Inga A1 - Lachniet, Matthew S. A1 - Lechleitner, Franziska A. A1 - Lorrey, Andrew A1 - Markowska, Monika A1 - Nehme, Carole A1 - Novello, Valdir F. A1 - Oster, Jessica A1 - Perez-Mejias, Carlos A1 - Pickering, Robyn A1 - Sekhon, Natasha A1 - Wang, Xianfeng A1 - Warken, Sophie A1 - Atkinson, Tim A1 - Ayalon, Avner A1 - Baldini, James A1 - Bar-Matthews, Miryam A1 - Bernal, Juan Pablo A1 - Boch, Ronny A1 - Borsato, Andrea A1 - Boyd, Meighan A1 - Brierley, Chris A1 - Cai, Yanjun A1 - Carolin, Stacy A1 - Cheng, Hai A1 - Constantin, Silviu A1 - Couchoud, Isabelle A1 - Cruz, Francisco A1 - Denniston, Rhawn A1 - Dragusin, Virgil A1 - Duan, Wuhui A1 - Ersek, Vasile A1 - Finne, Martin A1 - Fleitmann, Dominik A1 - Fohlmeister, Jens Bernd A1 - Frappier, Amy A1 - Genty, Dominique A1 - Holzkamper, Steffen A1 - Hopley, Philip A1 - Johnston, Vanessa A1 - Kathayat, Gayatri A1 - Keenan-Jones, Duncan A1 - Koltai, Gabriella A1 - Li, Ting-Yong A1 - Lone, Mahjoor Ahmad A1 - Luetscher, Marc A1 - Mattey, Dave A1 - Moreno, Ana A1 - Moseley, Gina A1 - Psomiadis, David A1 - Ruan, Jiaoyang A1 - Scholz, Denis A1 - Sha, Lijuan A1 - Smith, Andrew Christopher A1 - Strikis, Nicolas A1 - Treble, Pauline A1 - Unal-Imer, Ezgi A1 - Vaks, Anton A1 - Vansteenberge, Stef A1 - Voarintsoa, Ny Riavo G. A1 - Wong, Corinne A1 - Wortham, Barbara A1 - Wurtzel, Jennifer A1 - Zhang, Haiwei T1 - Evaluating model outputs using integrated global speleothem records of climate change since the last glacial JF - Climate of the past : an interactive open access journal of the European Geosciences Union N2 - Although quantitative isotope data from speleothems has been used to evaluate isotope-enabled model simulations, currently no consensus exists regarding the most appropriate methodology through which to achieve this. A number of modelling groups will be running isotope-enabled palaeoclimate simulations in the framework of the Coupled Model Intercomparison Project Phase 6, so it is timely to evaluate different approaches to using the speleothem data for data–model comparisons. Here, we illustrate this using 456 globally distributed speleothem δ18O records from an updated version of the Speleothem Isotopes Synthesis and Analysis (SISAL) database and palaeoclimate simulations generated using the ECHAM5-wiso isotope-enabled atmospheric circulation model. We show that the SISAL records reproduce the first-order spatial patterns of isotopic variability in the modern day, strongly supporting the application of this dataset for evaluating model-derived isotope variability into the past. However, the discontinuous nature of many speleothem records complicates the process of procuring large numbers of records if data–model comparisons are made using the traditional approach of comparing anomalies between a control period and a given palaeoclimate experiment. To circumvent this issue, we illustrate techniques through which the absolute isotope values during any time period could be used for model evaluation. Specifically, we show that speleothem isotope records allow an assessment of a model's ability to simulate spatial isotopic trends. Our analyses provide a protocol for using speleothem isotope data for model evaluation, including screening the observations to take into account the impact of speleothem mineralogy on δ18O values, the optimum period for the modern observational baseline and the selection of an appropriate time window for creating means of the isotope data for palaeo-time-slices. Y1 - 2019 U6 - https://doi.org/10.5194/cp-15-1557-2019 SN - 1814-9324 SN - 1814-9332 VL - 15 IS - 4 SP - 1557 EP - 1579 PB - Copernicus CY - Göttingen ER -