Spatio-temporal assessment of long-term historical wave simulation using MIROC6 wind dataset; A global scale study

Bahareh Kamranzad, Kyoto University, ​Graduate School of Advanced Integrated Studies in Human Survivability, Kyoto, Japan, Hiroaki Tatebe, JAMSTEC Japan Agency for Marine-Earth Science and Technology, Research Center for Environmental Modeling and Application, Yokohama, Japan and Kaoru Treasure Takara, Kyoto University, Graduate School of Advanced Integrated Studies in Human Survivability, Kyoto, Japan
Abstract:
The sixth version of the Model for Interdisciplinary Research on Climate (MIROC6) provides 160 years of historical wind dataset from 1850 to 2014. The long-term availability of wind dataset provides the opportunity to generate the long-term historical wave, which is vital for purposes such as extreme value analysis and long-term wave energy assessment. Moreover, access to long-term wave dataset can reduce the uncertainties by considering the climate variability in a longer time span. However, historical simulations of MIROC6 are not re-analysis dataset and hence, short-term variations may not be consistent with observations. In this study, MIROC6 wind-driven wave dataset was evaluated during the overlapping time with several resources; satellite observation, a global hindcast using JRA-55 wind field (KU-GLB wave) and ERA-5 wave dataset. In order to investigate the reliability of the modeled wave in intra-annual scales, monthly mean values of significant wave heights were compared in the whole globe, spatio-temporally. Assessment of temporal variation in monthly scale indicated consistency between MIROC6 wind-driven wave and satellite data, KU-GLB wave and ERA-5 wave. The spatial distribution of monthly mean significant wave height obtained from MIROC6 wind-driven wave and KU-GLB wave shows an overestimation in the Northern Pacific and Equatorial regions in a few months compared to satellite measurements and ERA-5 wave dataset. MIROC6 wind-driven monthly mean wave height indicates consistency with satellite measurements and ERA-5 wave data in Southern Hemisphere, while KU-GLB wave, despite using a re-analysis wind dataset, overestimates the wave height there. The results show that using MIROC6 for generating the wave characteristics is reliable mainly for the Southern Hemisphere, while the model parameters need tuning to be calibrated, especially for the Northern Hemisphere, although the temporal variation indicates consistency with the other sources of wave dataset.
Back to: Impacts of Interbasin Interaction on Climate Variability and Extreme Events II Posters