Wave-breaking modulation by infragravity waves during an extreme typhoon

Yoshinao Matsuba; Takenori Shimozono; Shinji Sato

doi:10.1371/journal.pone.0231242

Wave-breaking modulation by infragravity waves during an extreme typhoon

PLoS One. 2020 Apr 14;15(4):e0231242. doi: 10.1371/journal.pone.0231242. eCollection 2020.

Authors

Yoshinao Matsuba¹, Takenori Shimozono¹, Shinji Sato²

Affiliations

¹ Department of Civil Engineering, University of Tokyo, Tokyo, Japan.
² School of Systems Engineering, Kochi University of Technology, Kochi, Japan.

Abstract

Herein, we present coastal-wave records under historically extreme conditions caused by a strong typhoon in Japan in 2017. The extreme typhoon generated large infragravity waves, reaching a height of 2 m in shallow water. We took advantage of the extraordinary conditions to analyze the effect of the energetic infragravity waves on the nearshore evolution of relatively short waves. Individual wave analyses clearly demonstrate that the instantaneous water-level rise and drawdown caused by the infragravity waves alternately decelerated and accelerated the breaking of short waves under extreme conditions. This mechanism transmitted the large short-wave energy on the infragravity wave crests to the shore, eventually increasing the height of the nearshore waves. This study provides in situ evidence that the infragravity waves significantly affect nearshore wave characteristics under extreme conditions.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cyclonic Storms*
Disasters
Environmental Monitoring / methods*
Japan
Water

Substances

Water

Grants and funding

YM was supported by JSPS KAKENHI (Grant No. JP18J21135) and SS was supported by the JSPS-STINT Japan-Sweden Bilateral Joint Research Project. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.