Toward a Hydrodynamic Definition of the Strength of a Coastal Storm: The Coastal Storm Impulse (COSI) Parameter

In the US, the Saffir-Simpson(S-S) wind speed scale for hurricanes is misleading the public regarding the strength of a coastal storm for flooding events. The Coastal Storm Impulse (COSI) parameter is based on hydrodynamic, conservation of momentum principles; and it combines storm waves, storm surge, storm currents, and storm duration into one number for a specific location and storm event. This paper summarizes the modified COSI parameter, ongoing, and planned future research efforts. Although based on the US need to supplement the wind-based, S-S scale with a potential flooding and wave strength scale, the results could be applied world-wide to quantify the hydrodynamic strength of a coastal storm.