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Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Environmental Science / Faculty of Environmental Earth Science >
Peer-reviewed Journal Articles, etc >
Intra-annual variations in atmospheric dust and tritium in the North Pacific region detected from an ice core from Mount Wrangell, Alaska
| Title: | Intra-annual variations in atmospheric dust and tritium in the North Pacific region detected from an ice core from Mount Wrangell, Alaska |
| Authors: | Yasunari, Teppei J. Browse this author | | Shiraiwa, Takayuki Browse this author | | Kanamori, Syosaku Browse this author | | Fujii, Yoshiyuki Browse this author | | Igarashi, Makoto Browse this author | | Yamazaki, Koji Browse this author →KAKEN DB | | Benson, Carl S. Browse this author | | Hondoh, Takeo Browse this author →KAKEN DB |
| Keywords: | dust | | tritium | | ice core |
| Issue Date: | 19-May-2007 |
| Publisher: | American Geophysical Union |
| Journal Title: | Journal of Geophysical Research |
| Volume: | 112 |
| Issue: | D10 |
| Start Page: | D10208 |
| Publisher DOI: | 10.1029/2006JD008121 |
| Abstract: | The North Pacific is subject to various seasonal climate phenomena and material circulations. Therefore intra-annual ice core data are necessary for an assessment of the climate variations. To assess past variations, a 50-m ice core was drilled at the summit of Mount Wrangell Volcano, Alaska. The dust number, tritium concentrations, and stable hydrogen isotope were analyzed. The period covered was from 1992 to 2002. We found that the concentrations of both fine dust (0.52–1.00 μm), an indicator of long-range transport, and coarse dust (1.00–8.00 μm) increased together every spring. Moreover, their concentrations increased drastically after 2000, corresponding to the recent increase in Asian dust outbreaks in spring. Additionally, an increase in the spring of 2001 corresponded to the largest dust storm recorded in east Asia since 1979. Therefore our findings imply that Asian dust strongly polluted Mount Wrangell every spring. The stratospheric tracer, tritium, had late spring maxima almost every year, and we found this useful for ice core dating to identify late spring in the North Pacific region. We also found that a high positive annual correlation existed between the calculated tritium and fine dust fluxes from late spring to summer. We propose that an annual relationship between the stratosphere-troposphere exchange and Asian dust storm are most closely connected in late spring because their activities are weak in summer. The Mount Wrangell ice core is important and useful for assessing the dust and tritium circulation in the distant past around the North Pacific with probable intra-annual timescale information. |
| Rights: | An edited version of this paper was published by AGU. Copyright 2007, American Geophysical Union, JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 112. |
| Type: | article (author version) |
| URI: | http://hdl.handle.net/2115/26404 |
| Appears in Collections: | 環境科学院・地球環境科学研究院 (Graduate School of Environmental Science / Faculty of Environmental Earth Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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Submitter: 安成 哲平
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