Bir-Uja Cave, Kyrgyzstan 900 Year Stalagmite Isotope and Sr/Ca Data Fohlmeister, J.; Plessen, B.; Dudashvili, A.S.; Tjallingii, R.; Wolff, C.; Gafurov, A.; Cheng, H. Fohlmeister, J. Plessen, B. Dudashvili, A.S. Tjallingii, R. Wolff, C. Gafurov, A. Cheng, H. North Atlantic Oscillation earth science/paleoclimate/speleothems (depth,null,null,millimeter,null,speleothems,null,null,N,null) earth science/paleoclimate/speleothems (strontium/calcium,calcium carbonate,null,dimensionless,null,speleothems,raw,energy-dispersive x-ray fluorescence spectroscopy,N,ratio x1000) earth science/paleoclimate/speleothems (delta 18O,calcium carbonate,null,per mil VPDB,null,speleothems,corrected,isotope ratio mass spectrometry,N,time series corrected for 'in-cave' fractionation effects) earth science/paleoclimate/speleothems (age,null,null,year Common Era,null,speleothems,null,null,N,null) earth science/paleoclimate/speleothems (delta 13C,calcium carbonate,null,per mil VPDB,null,speleothems,raw,isotope ratio mass spectrometry,N,null) earth science/paleoclimate/speleothems earth science/paleoclimate/speleothems earth science/paleoclimate/speleothems (Bir-Uja Cave>LATITUDE 40.4833>LONGITUDE 72.5833) The strength of the North Atlantic Oscillation (NAO) is considered to be the main driver of climate changes over the European and western Asian continents throughout the last millennium. For example, the predominantly warm Medieval Climate Anomaly (MCA) and the following cold period of the Little Ice Age (LIA) over Europe have been associated with long-lasting phases with a positive and negative NAO index. Its climatic imprint is especially pronounced in European winter seasons. However, little is known about the influence of NAO with respect to its eastern extent over the Eurasian continent. Here we present speleothem records (d13C, d18O and Sr/Ca) from the southern rim of Fergana Basin (Central Asia) revealing annually resolved past climate variations during the last millennium. The age control of the stalagmite relies on radiocarbon dating as large amounts of detrital material inhibit accurate 230Th dating. Present-day calcification of the stalagmite is most effective during spring when the cave atmosphere and elevated water supply by snow melting and high amount of spring precipitation provide optimal conditions. Seasonal precipitation variations cause changes of the stable isotope and Sr/Ca compositions. The simultaneous changes in these geochemical proxies, however, give also evidence for fractionation processes in the cave. By disentangling both processes, we demonstrate that the amount of winter precipitation during the MCA was generally higher than during the LIA, which is in line with climatic changes linked to the NAO index but opposite to the higher mountain records of Central Asia. Several events of strongly reduced winter precipitation are observed during the LIA in Central Asia. These dry winter events can be related to phases of a strong negative NAO index and all results reveal that winter precipitation over the central Eurasian continent is tightly linked to atmospheric NAO modes by the westerly wind systems. STUDY NOTES: Speleothem oxygen and carbon isotope and trace element records from Bir-Uja Cave, Kyrgyzstan, Central Asia NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Fohlmeister, J. Investigator : Plessen, B. Investigator : Dudashvili, A.S. Investigator : Tjallingii, R. Investigator : Wolff, C. Investigator : Gafurov, A. Investigator : Cheng, H. 2017-11-15 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/23083 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/kyrgyzstan/bir-uja2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/kyrgyzstan/bir-uja2017sr-ca.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/kyrgyzstan/bir-uja2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/kyrgyzstan/bir-uja2017sr-ca.txt English https://www.ncdc.noaa.gov/paleo/study/23083 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/kyrgyzstan/bir-uja2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/kyrgyzstan/bir-uja2017sr-ca.txt Jens Fohlmeister, Birgit Plessen, Alexey Sergeevich Dudashvili, Rik Tjallingii, Christian Wolff, Abror Gafurov, Hai Cheng2017Winter precipitation changes during the Medieval Climate Anomaly and the Little Ice Age in arid Central AsiaQuaternary Science Reviews17824-3610.1016/j.quascirev.2017.10.026http://www.sciencedirect.com/science/article/pii/S0277379117308491 START YEAR: 1149 AD * END YEAR: 2011 AD 72.5833 40.4833 72.5833 40.4833