Zobrazeno 1 - 10
of 58
pro vyhledávání: '"I. Oyabu"'
Publikováno v:
The Cryosphere, Vol 18, Pp 425-449 (2024)
To better understand the near-surface evolution of polar firn in low-accumulation areas ( mm w.e. yr−1), we investigated the physical properties – density, microstructural anisotropy of ice matrix and pore space, and specific surface area (SSA)
Externí odkaz:
https://doaj.org/article/487f9f62ee2d4d69b6345f488ad6d52c
Autor:
C. Buizert, S. Shackleton, J. P. Severinghaus, W. H. G. Roberts, A. Seltzer, B. Bereiter, K. Kawamura, D. Baggenstos, A. J. Orsi, I. Oyabu, B. Birner, J. D. Morgan, E. J. Brook, D. M. Etheridge, D. Thornton, N. Bertler, R. L. Pyne, R. Mulvaney, E. Mosley-Thompson, P. D. Neff, V. V. Petrenko
Publikováno v:
Climate of the Past, Vol 19, Pp 579-606 (2023)
Here we present a newly developed ice core gas-phase proxy that directly samples a component of the large-scale atmospheric circulation: synoptic-scale pressure variability. Surface pressure changes weakly disrupt gravitational isotopic settling in t
Externí odkaz:
https://doaj.org/article/51b9134e3ba344ee9899a487aecf1ada
Autor:
I. Oyabu, K. Kawamura, S. Fujita, R. Inoue, H. Motoyama, K. Fukui, M. Hirabayashi, Y. Hoshina, N. Kurita, F. Nakazawa, H. Ohno, K. Sugiura, T. Suzuki, S. Tsutaki, A. Abe-Ouchi, M. Niwano, F. Parrenin, F. Saito, M. Yoshimori
Publikováno v:
Climate of the Past, Vol 19, Pp 293-321 (2023)
We reconstructed surface mass balance (SMB) around Dome Fuji, Antarctica, over the last 5000 years using the data from 15 shallow ice cores and seven snow pits. The depth–age relationships for the ice cores were determined by synchronizing them wit
Externí odkaz:
https://doaj.org/article/ee23281851664cd9a46fc3722598a15e
Autor:
S. Tsutaki, S. Fujita, K. Kawamura, A. Abe-Ouchi, K. Fukui, H. Motoyama, Y. Hoshina, F. Nakazawa, T. Obase, H. Ohno, I. Oyabu, F. Saito, K. Sugiura, T. Suzuki
Publikováno v:
The Cryosphere, Vol 16, Pp 2967-2983 (2022)
The retrieval of continuous ice core records of more than 1 Myr is an important challenge in palaeo-climatology. For identifying suitable sites for drilling such ice, knowledge of the subglacial topography and englacial layering is crucial. For this
Externí odkaz:
https://doaj.org/article/b56f92c11ec1461d84c2b846790d9c2b
Autor:
G. Lee, J. Ahn, H. Ju, F. Ritterbusch, I. Oyabu, C. Buizert, S. Kim, J. Moon, S. Ghosh, K. Kawamura, Z.-T. Lu, S. Hong, C. H. Han, S. D. Hur, W. Jiang, G.-M. Yang
Publikováno v:
The Cryosphere, Vol 16, Pp 2301-2324 (2022)
In blue-ice areas (BIAs), deep ice is directly exposed at the surface, allowing for the cost-effective collection of large-sized old-ice samples. However, chronostratigraphic studies on blue-ice areas are challenging owing to fold and fault structure
Externí odkaz:
https://doaj.org/article/d12aaaf0c2c04e03a7fb9bca92999fb0
Autor:
T. Umezawa, S. Sugawara, K. Kawamura, I. Oyabu, S. J. Andrews, T. Saito, S. Aoki, T. Nakazawa
Publikováno v:
Atmospheric Chemistry and Physics, Vol 22, Pp 6899-6917 (2022)
Systematic measurements of atmospheric methane (CH4) mole fractions at the northern high latitudes only began in the early 1980s. Although CH4 measurements from Greenland ice cores consistently covered the period before ∼ 1900, no reliable observat
Externí odkaz:
https://doaj.org/article/e69dc28cc5cb4a14b86e13c706743803
Autor:
I. Oyabu, K. Kawamura, T. Uchida, S. Fujita, K. Kitamura, M. Hirabayashi, S. Aoki, S. Morimoto, T. Nakazawa, J. P. Severinghaus, J. D. Morgan
Publikováno v:
The Cryosphere, Vol 15, Pp 5529-5555 (2021)
The variations of δO2/N2 and δAr/N2 in the Dome Fuji ice core were measured from 112 m (bubbly ice) to 2001 m (clathrate hydrate ice). Our method, combined with the low storage temperature of the samples (−50 ∘C), successfully excludes post-cor
Externí odkaz:
https://doaj.org/article/d0059c1a940546db8ff04f38ad24d920
Autor:
I. Oyabu, K. Kawamura, K. Kitamura, R. Dallmayr, A. Kitamura, C. Sawada, J. P. Severinghaus, R. Beaudette, A. Orsi, S. Sugawara, S. Ishidoya, D. Dahl-Jensen, K. Goto-Azuma, S. Aoki, T. Nakazawa
Publikováno v:
Atmospheric Measurement Techniques, Vol 13, Pp 6703-6731 (2020)
Air in polar ice cores provides unique information on past climatic and atmospheric changes. We developed a new method combining wet extraction, gas chromatography and mass spectrometry for high-precision, simultaneous measurements of eight air compo
Externí odkaz:
https://doaj.org/article/1245e4bff01c47058f49d1749e5ad518
Autor:
L. Menviel, E. Capron, A. Govin, A. Dutton, L. Tarasov, A. Abe-Ouchi, R. N. Drysdale, P. L. Gibbard, L. Gregoire, F. He, R. F. Ivanovic, M. Kageyama, K. Kawamura, A. Landais, B. L. Otto-Bliesner, I. Oyabu, P. C. Tzedakis, E. Wolff, X. Zhang
Publikováno v:
Geoscientific Model Development, Vol 12, Pp 3649-3685 (2019)
The penultimate deglaciation (PDG, ∼138–128 thousand years before present, hereafter ka) is the transition from the penultimate glacial maximum (PGM) to the Last Interglacial (LIG, ∼129–116 ka). The LIG stands out as one of the warmest in
Externí odkaz:
https://doaj.org/article/18253b620b794af5914d7399ce1cda4b
Greenland records of aerosol source and atmospheric lifetime changes from the Eemian to the Holocene
Autor:
S. Schüpbach, H. Fischer, M. Bigler, T. Erhardt, G. Gfeller, D. Leuenberger, O. Mini, R. Mulvaney, N. J. Abram, L. Fleet, M. M. Frey, E. Thomas, A. Svensson, D. Dahl-Jensen, E. Kettner, H. Kjaer, I. Seierstad, J. P. Steffensen, S. O. Rasmussen, P. Vallelonga, M. Winstrup, A. Wegner, B. Twarloh, K. Wolff, K. Schmidt, K. Goto-Azuma, T. Kuramoto, M. Hirabayashi, J. Uetake, J. Zheng, J. Bourgeois, D. Fisher, D. Zhiheng, C. Xiao, M. Legrand, A. Spolaor, J. Gabrieli, C. Barbante, J.-H. Kang, S. D. Hur, S. B. Hong, H. J. Hwang, S. Hong, M. Hansson, Y. Iizuka, I. Oyabu, R. Muscheler, F. Adolphi, O. Maselli, J. McConnell, E. W. Wolff
Publikováno v:
Nature Communications, Vol 9, Iss 1, Pp 1-10 (2018)
Past climate changes in Greenland ice were accompanied by large aerosol concentration changes. Here, the authors show that by correcting for transport effects, reliable source changes for biogenic aerosol from North America, sea salt aerosol from the
Externí odkaz:
https://doaj.org/article/cd21059449ce4188baac9393e1761940