Meteotsunami Events and Hydrologic Response in an Isolated Wetland:
Beaver Island in Lake Michigan, USA
Abstract
Meteotsunamis are both a well-known and poorly understood phenomenon. In
particular, the influence of and disturbance by meteotsunami on coastal
wetlands is largely unknown. This paper documents a case illustrating
how water levels in an isolated wetland, specifically an incipient
foredune/swale complex, in northern Lake Michigan responded to a
meteotsunami event. We identified potential meteotsunami influence on
wetland water levels through slope-break analysis, verified the presence
of meteotsunami waves at surrounding lake water level gauge stations
with wavelet analysis, analyzed both regional and small-scale
meteorological data to establish what source of atmospheric forcing
resulted in meteotsunami formation, and used a hydrodynamic model to
simulate lake surface response and meteotsunami generation. Here, we
present what we hypothesize reflects an idealized response of wetland
water levels to meteotsunami influence where an atmospheric bore
propagating away from a convective system formed a meteotsunami event
that was captured in subsurface water levels beneath the isolated
wetland. While this event produced an obvious response, the potential
for multiple sources of meteorological forcing and secondary wave
refraction highlights several of the challenges with predicting
generation of and hazard from meteotsunami events. These issues equally
translate in how the current methodology can be applied to isolated
wetland systems. The event presented in this study make a strong case
for focused research on coastal wetland response to meteotsunamis (and
meteotsunami-like events) to address this understudied impact given its
implications for coastal processes and resiliency.