11:30 AM - 11:45 AM
[AOS19-04] Effect of Vertical Land Movement on Coastal Sea Level Rise in Japan
Keywords:coastal sea level rise in Japan, vertical land movement
Sea level rise (SLR) due to global warming is a very serious problem for Japan, where large cities are concentrated along the coast. The main causes of global SLR are the expansion of seawater and the melting of ice sheets. In addition, local SLR must take into account the effects of vertical land motion (VLM) in addition to the dynamic response caused by wind and thermohaline forcing. Japan is a place where irregular VLMs are large and their magnitude is comparable to that of SLR. The effects of VLMs are discussed in the Japan Climate Change 2025 report to be published this year. Here, we follow the discussion of Nakano et al. (2023) and consider the effects of VLMs on coastal SLR in Japan.
Observations of coastal SLR in Japan are based on about 16 representative tidal systems.
The time series since the beginning of the 20th century are dominated by a 50-year cycle with a clear peak in the 1950s, while the global mean estimates show a consistent upward trend with decades-long variations. The calculated time series of the standard deviations of the deviations from the mean for each tide gauge show a behavior that can be explained by a model in which each tide gauge station is subject to constant crustal deformation of different magnitude. These results suggest that there is a reasonable suspicion that, despite efforts to suppress the effects of ground deformation, the tide gauge data are significantly affected by it in the long term.
Observations of coastal SLR in Japan are based on about 16 representative tidal systems.
The time series since the beginning of the 20th century are dominated by a 50-year cycle with a clear peak in the 1950s, while the global mean estimates show a consistent upward trend with decades-long variations. The calculated time series of the standard deviations of the deviations from the mean for each tide gauge show a behavior that can be explained by a model in which each tide gauge station is subject to constant crustal deformation of different magnitude. These results suggest that there is a reasonable suspicion that, despite efforts to suppress the effects of ground deformation, the tide gauge data are significantly affected by it in the long term.