Project/Area Number |
07408001
|
Research Category |
Grant-in-Aid for Scientific Research (A)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
自然地理学
|
Research Institution | TOKYO METROPOLITAN UNIVERSITY |
Principal Investigator |
MIKAMI Takehiko TOKYO METROPOLITAN UNIVERSITY,Professor, 理学研究科, 教授 (10114662)
|
Co-Investigator(Kenkyū-buntansha) |
WATANABE Makiko TOKYO METROPOLITAN UNIVERSITY, 総合理工学研究科, 助教授 (10175119)
YOSHIMURA Minoru TOKYO METROPOLITAN UNIVERSITY, 教育学部, 教授 (40020375)
KAWAMURA Kimitaka TOKYO METROPOLITAN UNIVERSITY, 低温科学研究所, 教授 (70201449)
FUKUSAWA Hitoshi TOKYO METROPOLITAN UNIVERSITY, 理学研究科, 助教授 (80208933)
|
Project Period (FY) |
1995 – 1997
|
Project Status |
Completed (Fiscal Year 1997)
|
Budget Amount *help |
¥16,800,000 (Direct Cost: ¥16,800,000)
Fiscal Year 1997: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1996: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1995: ¥13,700,000 (Direct Cost: ¥13,700,000)
|
Keywords | Lake Suwa / climatic variation / lake sediments / Omiwatari / お神渡り / 有機炭素 / 小氷期 |
Research Abstract |
In the summer of 1996, we extracted 2m long (around 800 years) sediment core samples from Lake Suwa using a piston corer. Sampled lake sediments were sliced in every 2.5 cm to analyze the color quality, the magnetized ratio, the specific gravity, the mineral composition, and the content of carbon, nitrogen and sulfur. The results show that organic carbon content is an effective indicator of climatic variations. Thus we examine the relationship between the organic carbon content of Lake sediment cores and the freezing dates of Lake Suwa for the last 500 years. An attempt was made to estimate winter temperatures based on the long term record of the freezing dates of Lake Suwa using the linear regression equation (r=0.80). Estimated winter temperature time-series indicated that early 1600's was a coldest period, whereas both 1480's and 1540's were relatively warm. Temperature showed increasing trend from 1750's to 1860's, during which severe famine occurred frequently in Japan.
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