Project/Area Number |
13490002
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
広領域
|
Research Institution | HOKKAIDO UNIVERSITY |
Principal Investigator |
KAWAMURA Toshiyuki HOKKAIDO UNIVERSITY, Hokkaido Univ., Inst. of Low Temperature Sci., Assistant Prof. (50091434)
|
Co-Investigator(Kenkyū-buntansha) |
ISHIKAWA Nobuyoshi Hokkaido Univ., Inst. of Low Temperature Sci., Asso. Prof. (70002277)
SHIRASAWA Kunio Hokkaido Univ., Inst. of Low Temperature Sci., Asso. Prof. (50196622)
TOYOTA Takenobu Hokkaido Univ., Inst. Low Temperature Sci., Assistant Prof. (80312411)
|
Project Period (FY) |
2001 – 2003
|
Project Status |
Completed (Fiscal Year 2003)
|
Budget Amount *help |
¥7,700,000 (Direct Cost: ¥7,700,000)
Fiscal Year 2003: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2002: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2001: ¥4,900,000 (Direct Cost: ¥4,900,000)
|
Keywords | sea ice / columnar ice / granular ice / radiation / radiative property / permeant property / 海水 |
Research Abstract |
Sea ice in the Arctic Ocean has predominantly columnar structure. However, from recent studies conducted in the seasonal ice zone, e.g. Antarctic Oceans and the Okhotsk Sea, it is found that ice with granular structure was dominant at the zone. The contribution to sea ice growth has become of major interest. It is expected that the difference of the ice structure would cause difference of physical properties, e.g. growth processes, radiation and permeability. We tried to clarify the difference of the physical properties between the above two difference of the ice types both experimental and field observations. Experimental study was conducted in the Cryospheric Environment Simulator, a highly equipped cold laboratory, at Shinjo Branch, Nagaoka Institute of Snow and Ice Studies, National Research Institute for Earth Science and Disaster Prevention. We grew sea ice with the ice types in two stirred/unstirred water tanks. Snow ice, a kind of granular ice, was grown from snow accumulated by an artificial snow machine in the two tanks. Occasionally we observed the features of sea ice growth during the experiment. We also conducted radiation measurements, i.e. albedo and attenuation coefficient. After the experiments, we observed the ice structure and measured density, salinity and isotopic compositions. Field observation was carried out on a line from the mouth of a river to the opening in the eastern part of Lake Saroma. The aim of the observation is to investigate change of sea ice structure with the parent water salinity and contribution of both snow and structural ice types. We also measured permeability difference with ice structure.
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