Modeling the contribution of M 2 tidal amplification to the Holocene rise of mean high water in the Gulf of Maine and the Bay of Fundy

Abstract

Increase in the M 2 (principal lunar semi-diurnal) component of the tidal range is an important contributor to the postglacial rise of the high-tide level in the Gulf of Maine and the Bay of Fundy in addition to relative sea-level rise. The increase occurred as the shape of this semi-enclosed embayment changed with sea-level rise and its natural period approached resonance with the M 2 tide. A three-dimensional tide model (3DENS) predicts the following M 2 tidal ranges averaged for the Gulf of Maine/Bay of Fundy as a percentage of the present range: 54–59% at 7000 yrs B.P., 73% at 5000 yrs B.P., 78% at 4000 yrs B.P., 85% at 3000 yrs B.P., 94% at 2000 yrs B.P., and 98% at 1000 yrs B.P. With a predicted sea-level rise of 0.15–0.90 m by the year 2100, M2 tidal range may increase 0.3–1.9%.