2023 Fiscal Year Research-status Report
Predicting river discharge in mountainous river basins during heavy rain events using seismic noise data
| Project/Area Number |
22K03742
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| Research Institution | National Research Institute for Earth Science and Disaster Prevention |
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Principal Investigator |
P.C. Shakti 国立研究開発法人防災科学技術研究所, 水・土砂防災研究部門, 主任専門研究員 (60863553)
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| Co-Investigator(Kenkyū-buntansha) |
澤崎 郁 国立研究開発法人防災科学技術研究所, 地震津波火山ネットワークセンター, 主任専門研究員 (30707170)
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| Project Period (FY) |
2022-04-01 – 2025-03-31
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| Keywords | River discharge / Noise data / Hi-net / Flow estimation / Flood events / Hydrological simulation / River basins / Flood risk |
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| Outline of Annual Research Achievements |
The objective of this study is to use seismic data to estimate river discharge, particularly during floods in mountainous river basins, integrating the disciplines of Hydrology and Seismology. After reviewing Hi-net noise observations and the availability of hydrological data, we selected certain river basins for analysis. In these basins, we conducted hydrological simulations to analyze flood dynamics and investigated correlations between Hi-net noise and river flow data during flood events. Additionally, we evaluated how seismic noise data across different frequency ranges correlated with the simulated discharge data during floods.
Our findings indicate that a strong correlation holds significance in mountainous regions characterized by steep riverbed slope. Furthermore, we observed that this correlation is particularly distinct within the 1-2 Hz frequency range. This phenomenon occurs because microseisms contaminate noise below 1 Hz, while noise energy above 2 Hz undergoes significant attenuation during propagation, thereby limiting its long-distance propagation. We continued our investigation into the link between seismic data and river flow, thereby expanding our understanding of these interactions.
Portions of this research were presented at national and international conferences, published in journals articles/proceedings. Part of this study was also highlighted in the Science Japan magazine, published by the Japan Science and Technology Agency (JST), specifically within the section on 'International Brain Circulation and Japan's initiatives to foster it.'
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| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
In this study, we have analyzed observed seismic noise data (Hi-net) and simulated river discharge to reach our objectives. Discovering key insights from the analysis of these diverse data sets, each serving different purposes and disciplines, proved both challenging and fascinating. We processed Hi-net data from various stations across different river basins for historical events and conducted hydrological simulations to extract river discharge data for those events in the selected basins. We have regularly been sharing and presenting our results with national and international academic societies.
We are in the time line of projects. However, publishing our all results with summarizing them may takes slightly long time depending up on the processing time of journal types. Util the date, we have not experienced any difficulties to carry on our research. Currently, we are analyzing long-term Hi-net and simulated river discharge data across various stations in several mountainous river basins. We anticipate finalizing our results later this year, as scheduled in our project timeline.
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| Strategy for Future Research Activity |
The objective of this study is to demonstrate how seismic data can be used to estimate river discharge, with a particular focus on flood conditions in mountainous river basins. This research is based on the interdisciplinary subjects i.e., Hydrology and Seismology. We conducted hydrological simulations of several river basins in Japan, considering various flood scenarios. A comparative analysis was performed between the simulated river discharge and nearby Hi-net data across different frequency ranges in mountainous river basins. We will continue to study the modeling and verification of the physical mechanism of seismic noise and river discharge.
Based on the results we obtained in 2023 fiscal year; we are currently conducting a long-term analysis to predict river flow in mountainous river basins by correlating noise data with simulated river discharge. We aim to develop a suitable empirical relationship at some seismic stations to predict regular discharge time series. We anticipate establishing a strong correlation between Hi-net data and simulated river discharge at certain stations of mountainous river basins. Our research is progressing according to plan, and we intend to submit our research outcomes to peer-reviewed journals and present them at national/international conferences this year.
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| Causes of Carryover |
In our original research plan, we intended to attend various national and international conferences. However, we participated virtually in some conferences last year, resulting in underutilization of our allocated budget.
This year, our plan includes not only participating in national and international conferences but also publishing research articles, aiming to fully utilize the budgeted funds.
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| Remarks |
PI was interviewed, and details of this KAKENHI project, including PI's research summaries and opportunities, has been published in English, Japanese, and Chinese by Science Japan of JST.
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