Title: Temporal Changes in the Response of the Nodal Modulation of the M2 tide in the Gulf of Maine.

Journal: Continental Shelf Research, 186: 13-20.

Authors: PAN H. -D.*, Q. -X. Zheng，and X. -Q. Lv *

Abstract: Accurate estimation of the changes of tides is important for sea level prediction and fundamental for local coastal planning. Here we use a novel method, enhanced harmonic analysis (EHA), to extract temporal changes in the response of the nodal modulation of the M₂tide in the Gulf of Maine. The results show that the temporal variations of nodal amplitudes at four stations in the Gulf of Maine are similar from 1970s to 2013. They all increase in the 1970s to peak values in the 1985s and in the 2000s they decrease to minimum values. The North Atlantic Oscillation (NAO), which is one of the major climate modes in the North Atlantic Ocean, may be responsible for temporal changes in the response of the nodal modulation of the M₂tide from 1970s to 2013. Also, the results obtained by the new method indicate that the traditional method of harmonic analysis slightly underestimates the trend of M₂amplitude in the Gulf of Maine.