著者

Daisuke Komori Shinichirou Nakamura Masashi Kiguchi Asako Nishijima Dai Yamazaki Satoshi Suzuki Akiyuki Kawasaki Kazuo Oki Taikan Oki

出版者

水文・水資源学会/日本地下水学会/日本水文科学会/陸水物理研究会

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.6, pp.41-46, 2012 (Released:2012-04-28)

参考文献数

8

被引用文献数

52 159

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A massive flood, the maximum ever recorded in Thailand, struck the Chao Phraya River in 2011. The total rainfall during the 2011 rainy season was 1,439 mm, which was 143% of the average rainy season rainfall during the period 1982–2002. Although the gigantic Bhumipol and Sirikit dams stored approximately 10 billion m3 by early October, the total flood volume was estimated to be 15 billion m3. This flood caused tremendous damage, including 813 dead nationwide, seven industrial estates, and 804 companies with inundation damage, and total losses estimated at 1.36 trillion baht (approximately 3.5 trillion yen). The Chao Phraya River watershed has experienced many floods in the past, and floods on the same scale as the 2011 flood are expected to occur in the future. Therefore, to prepare of the next flood disaster, it is essential to understand the characteristics of the 2011 Chao Phraya River Flood. This paper proposes countermeasures for preventing major flood damage in the future.

著者

Yuki Kita Dai Yamazaki

出版者

Japan Society of Hydrology and Water Resources (JSHWR) / Japanese Association of Groundwater Hydrology (JAGH) / Japanese Association of Hydrological Sciences (JAHS) / Japanese Society of Physical Hydrology (JSPH)

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.17, no.2, pp.15-20, 2023 (Released:2023-04-01)

参考文献数

19

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Many studies have proved that hydrological extreme values estimated from decadal observation data and river inundation simulations are associated with various uncertainties; however, few studies have evaluated the uncertainties associated with internal climate variability. We used large-ensemble river inundation simulations to quantitatively evaluate uncertainties in river depth at the Takahama monitoring station and flood extent in the Yodo River basin. Using a single 60-year ensemble, the river depth for a 1,000-year return period (RP) flood scale have uncertainty between –11.7% and +9.2% in a 3,000-year flood simulation. Thus, the RP of the simulated river depth ranges from 207–3,441 years. To maintain the RP uncertainty within ±300 years would require a simulation of ≥1,200 years. The flood extent uncertainty with an RP of 1,000 years was found to be –8.4% and +7.6% based on a 3,000-year simulation for the lower Yodo River basin. According to this result, the RP of the simulated flood extent ranges from 340–3,060 years. These results suggest that the decadal data used in conventional flood risk analyses potentially contain large uncertainty related to internal climate variability in the RP for water depth and flood extent by approximately 0.3–3-fold.

著者

Yukiko Hirabayashi Haireti Alifu Dai Yamazaki ‪Gennadii Donchyts Yuki Kimura

出版者

Japan Society of Hydrology and Water Resources (JSHWR) / Japanese Association of Groundwater Hydrology (JAGH) / Japanese Association of Hydrological Sciences (JAHS) / Japanese Society of Physical Hydrology (JSPH)

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.15, no.2, pp.37-43, 2021 (Released:2021-06-22)

参考文献数

23

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Floods are major natural disasters that have considerable consequences worldwide. As the frequency and magnitude of flooding are expected to be affected by ongoing climate change, understanding their past changes is important for developing adequate adaptation measures. However, the limited spatiotemporal coverage of flood gauges hinders detection of changes in flooding, particularly in poorly gauged regions. Here, we propose a method using surface water data of river floodplain inundation as a proxy of the magnitude and frequency of flooding. Surface water data − Aqua Monitor which represented the probability linear trend changes in land and water surface area based on 30-m Landsat images between 1984–2000 and 2000–2013 was used in this study. The changes in water surface area over the floodplain obtained from Aqua Monitor showed high correspondence with historical trends observed or simulated annual maximum daily discharge, indicating the potential to detect changes in frequency and magnitude of flood from satellite data. In regions where changes could be measured with sufficient satellite images, 29% showed an increase in water surface area in the flood plain, 41% showed a decrease, and 30% showed small or no changes.