Japan Geoscience Union Meeting 2018

Presentation information

[EJ] Poster

A (Atmospheric and Hydrospheric Sciences) » A-CG Complex & General

[A-CG38] Science in the Arctic Region

Thu. May 24, 2018 1:45 PM - 3:15 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Shun Tsutaki(The University of Tokyo), NAOYA KANNA(Arctic Research Center, Hokkaido University), Shunsuke Tei(北海道大学 北極域研究センター, 共同), Tetsu Nakamura(Faculty of Environmental Earth Science, Hokkaido University)

[ACG38-P23] Understanding of hydrological circulation of Arctic region using 17O-excess variation in SIGMA-D ice core

*Akane Tsushima1, Kumiko Goto Azuma2, Sumito Matoba3, Naoko Nagatsuka2, Teruo Aoki4, Koji Fujita5 (1.Research Institute for Humanity and Nature, 2.National Institute of Polar Research, 3.Institute of Low Temperature Science, Hokkaido Univ.,, 4.Okayama Univ., 5.Nagoya Univ.)

Keywords:Ice core, 17O-excess, Greenland

The stable water isotope ratios (δ18O, δD and d-excess which is clculated from δD and δ18O) in ice cores are important proxy of paleo climate change. Recently, δ17O and 17O−excess which is clculated from δ18O and δ17O have attracted attention as a promising new proxy of hydro-climate variation. In this study, we measured δ17O, δ18O and δD in an ice core, which was obtained from the northwest Greenland using Wavelength-Scanned Cavity Ring-Down Spectroscopy (model L2140-i; Picarro) with high precision at the National Institute of Polar Research. And we also calculated d-excess and 17O-excess form those. For last 80 years, the correlation of 17O-excess and d-excess is definitely changed with period of 10 to 20 years. The correlation of those shifted in 1967, that is, we showed sea-level pressure in periods 1(1949-1967) and 2(1968-1980) (NCEP Reanalysis data provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their Web site at http://www.esrl.noaa.gov/psd/cgi-bin/data/composites/printpage.pl). During the periods 2, the high-pressure area extended across the whole Greenland, therefore, water vapor was hard to reach to SIDMA-D site. We think that the moisture influx route to SIGMA-D site and its amount changed due to the climate field change, resulting the changes of those correlations.