Atmospheric Groundwater Forcing of a Subterranean Estuary: A Seasonal Seawater Recirculation Process

Abstract

Here we isolate groundwater responses to atmospheric forcing of surface water levels by relating anomalies in coastal aquifer hydraulic head time‐series to weather events. Our results demonstrate that atmospheric forcing has a greater effect on groundwater exchange and extended residence time over astronomical tidal pumping at times. During winter, atmospheric groundwater forcing was associated with winter storm passage and had a recurrence interval of approximately 7 days. During summer, atmospheric groundwater forcing was limited to weak diurnal atmospheric convection and infrequent tropical cyclone activity. Because winter storms and tropical cyclones commonly produce precipitation, atmospheric groundwater forcing can synergize with the timing of meteoric recharge producing periods of intense submarine groundwater discharge.

Frequent Storm Surges Affect the Groundwater of Coastal Ecosystems

“…Beebe et al. (2022) estimated the consequences of a moderate storm on submarine groundwater discharge (SGD), with the formation of an anomalous seawater intrusion in the groundwater system. Wilson et al.…”

“…However, the coupling between hydrological processes and coastal ecosystems has not been studied in detail. Beebe et al (2022) estimated the consequences of a moderate storm on submarine groundwater discharge (SGD), with the formation of an anomalous seawater intrusion in the groundwater system. Wilson et al (2015) determined the magnitude and the main processes controlling temporal variations in tidally driven SGD caused by moderate storm surges.…”

“…Many studies have focused on the hydrological, ecological, and geomorphological consequences of hurricanes, characterized by large storm surges (Fagherazzi, Anisfeld, et al, 2019;Fagherazzi, Nordio, et al, 2019;Fernandes et al, 2018;Gardner et al, 2002;Middleton, 2016). Recently, more attention has been paid about the effects of frequent and moderate storm events on coastal areas (Beebe et al, 2022;Wilson et al, 2011Wilson et al, , 2015. However, the coupling between hydrological processes and coastal ecosystems has not been studied in detail.…”