Nonlinear Interaction Between the Tide and the Storm Surge with the Current due to the River Flow in the Río de la Plata

Abstract

The Río de la Plata estuary (RdP) is characterized by the large flow of its tributary rivers (Q), with an average of 22,000 m 3 s −1 and an interannual variability range from 8000 to 90,000 m 3 s −1 . In this work, the hypothesis that the current due to that flow (CDR) interacts nonlinearly with both the tides and storm surges is evaluated utilizing water level observations and numerical simulations. Two tide gauge time series gathered at the freshwater tidal zone (FTZ) of the RdP are analyzed with the novel surrogate analysis. The analysis is applied for periods of high, medium and low Q. Results show that both interactions occur at the upper half of the FTZ and increase with Q. Harmonic analyses support the surrogate analysis' conclusions and show that tide-CDR interaction redistributes the energy among tidal harmonics, increasing asymmetry. Numerical simulations confirm that (i) both interactions maximize at the upper half of the FTZ and decrease downstream; and (ii) they are modulated by Q; a rise of about 14,000 m 3 s −1 (interquartile range) can produce an intensification of 50% and 100% of the amplitudes of the tide-CDR and surge-CDR interactions, respectively; and (iii) both interactions introduce asymmetries in the water level, with faster rises and slower falls; (iv) the quadratic bottom friction is the main source of both interactions; (v) tide-CDR interaction represents 12% of the water level associated with the tide, whereas surge-CDR interaction accounts for 5% of the surge peak; and (vi) the interactions are significant in the upper FTZ because there, the magnitude of the currents associated with the tide and the surge are comparable to CDR; downstream, the channel widens and CDR decreases.

Development and evaluation of an ensemble forecast/hindcast system for storm surges in the Río de la Plata Estuary

“…Even though there are several tidal gauges inside the RdP (e.g., Dinápoli et al ., 2020c), Palermo is the only coastal station at the RdP with storm surge and extreme event thresholds and where a large continuous record of observations (from 1905 to the present) is available. It must be taken into account that Palermo is located at the uppermost and narrowest part of the estuary where the storm surge amplitudes (Simionato et al ., 2004) as well as the nonlinear tide–surge interactions (Dinápoli et al ., 2020b) and the nonlinear tide–river and surge–river interactions (Dinápoli et al ., 2020d) maximize. Therefore the station's data provide a good test of the model's ability to integrate the effect of the wind over the whole area of interest in this study (Meccia et al ., 2009).…”

“…The water level in the RdP is usually described as the combination of a semidiurnal microtidal regime with diurnal inequalities (D'Onofrio et al ., 2012) and the wind‐driven circulation (Simionato et al ., 2004, 2006a). Large nonlinear interactions occur between the tide, the surge and the river discharge (Etala, 2006a; Dinápoli et al ., 2020b; 2020d). Because of its large length and width, the tide propagates in the RdP as a Kelvin wave, entering the estuary from the south and exiting to the north (Simionato et al ., 2005).…”

Satellite and High-Spatio-Temporal Resolution Data Collected by Southern Elephant Seals Allow an Unprecedented 3D View of the Argentine Continental Shelf

“…The GEBCO 2019 portion of the ACS that we used has been corrected, considering bathymetry measurements provided by the Servicio de Hidrografia Naval. This version is currently the most used for regional numerical models in the region [26,53,54].…”

“…TPXO8 represents tides very well in the region [56]. It has also been used to implement regional models [26,54].…”

Characterizing the Non-linear Interactions Between Tide, Storm Surge, and River Flow in the Delaware Bay Estuary, United States

“…Although TSRIs are rarely studied, they are an important component of storm surges. For example, Dinapoli et al (2021) found that the current due to river flow (CDR) non-linearly interacts with both the tides and storm surges in the Río de la Plata estuary. Their work further suggests the tide-CDR and surge-CDR interactions both induce asymmetries in the water level and the interactions are mainly caused by the quadratic bottom friction.…”