Using observations of the 2011-Tohoku and some other tsunamis in rivers as a starting point for analytical and numerical exploration, this book suggests a basis for predicting tsunami impacts in a river after the wave has transitioned into the river’s channel.
About the Author
Elena Tolkova graduated from the Radiophysics department of the Nizhny Novgorod State University in Russia in 1985, and stayed with the University for 15 years after graduation -- first as a research associate/engineer, then as an assistant/associate professor -- while performing contract research, writing her dissertation, and teaching general physics, optics, and signal processing. Elena resumed her scientific career in the US in 2005, in the field of hydrodynamics. Elena worked as a research scientist at the University of Washington and a contractor at NOAA/Pacific Marine Environmental Laboratory, Seattle, helping to develop and implement a particular tsunami forecasting technology. In 2013, she continued her research at the NorthWest Research Associates, where she has developed an open-source numerical model (Cliffs) for simulating tsunami propagation and land inundation, co-authored a novel approach to using tsunami’s en-route measurements for tsunami predictions, and in collaboration with Prof. H. Tanaka and his team at Tohoku University, Japan, investigated some puzzling tsunami behaviors in rivers.
Table of Contents1. Observations of tsunamis in rivers.- How are tsunamis measured?.- Tsunami-induced water accumulation in rivers.- Tsunami modulation by tide: Columbia River.- Tsunami modulation by tide: 2010 Chile tsunami in rivers in Japan.- Bore as a typical tsunami waveform in a river.- 2. First analytical chapter: long wave set-up.- Cross-river integrated shallow-water equations.- Backwater curve of a steady flow.- Backwater set by an intruding wave.- 3. Like tsunamis, tides make rivers deeper.- Layman’s Physics: a positive disturbance penetrates farther.- Wave set-up in tidal observations.- Tidal wave set-up in the Yoshida River, Japan.- Tidal wave set-up in the Columbia River, USA.- Don’t tidal scientists know all that?.- 4. Tsunami and tidal set-up in rivers: a numerical study.- River models.- Quantifying a river’s response.- Simulation arrangements and results.- First look at the solutions.- Backwater: patterns, relations, numbers.- Two metrics for wave decay with distance travelled.- Back to the real world.- 5. Second analytical chapter: ascending with the wave.- Wave-locked slope, and a new form of the equations.- Unidirectional wave and steady flow.- When channel convergence balances friction.- Excursus into analytical treatment of estuarine tides.- Effect of tidal WLS on a small tsunami ascending a river.- 6. Tsunami rides tides.- Designated dataset: the 2015 Chile tsunami in rivers in Japan.- Metrics for a tsunami amplitude and for the tidal conditions.- Record’s components: tide, tsunami, background noise.- Correlation between an instant tsunami amplitude and WLS.- Methodology of admittance computations as a function of WLS.- When is a tsunami’s admittance into a tidal river greater?.- Physics of admittance variations with WLS.- 7. Tsunami Bores.- Shock Equations.- Giving up momentum correction coefficients.- Shock conditions in a channel with vertical banks.- Shock conditions in a channel with sloping shores.- Whose flow is faster?.- How does an ordinary wave become a bore?.- Turbulence or ripples?.- Shock reflection from a barrage: observations and analytics.- How good is this theory?.- The book’s main points