Impacts of Hurricane Irma on the Circulation and Transport in Florida Bay and the Charlotte Harbor Estuary

Abstract

Hurricane Irma impacted the coastal ocean and estuaries of west Florida as it transited the Florida peninsula from 10 to 12 September 2017, after making landfall first at Cudjoe Key as a Category 4 hurricane and then again at Naples, as a Category 2 hurricane. The response to Hurricane Irma is analyzed using both in situ data and a hindcast simulation by the West Florida Coastal Ocean Model (WFCOM). During the Irma passage, a negative storm surge followed by a positive surge occurred along the west Florida coast, with a recorded water level fluctuation of 3.31 m (from trough to peak) within Rookery Bay, and the negative surge with sea level set-downs (> 1 m) caused drying in Florida Bay and the Charlotte Harbor estuary. Irma-driven currents in Florida Bay, estimated to be 1.50-2.00 m/s, were strong enough to damage benthic communities. The resulting ocean circulation patterns and water exchange pathways are revealed by simulated Lagrangian trajectories. Also investigated is the memory of the coastal system. Whereas sea level and currents restored back to their normal fluctuations within a day, water temperature and salinity required several days to stabilize, and by virtue of heavy rainfall, excess freshwater input from rivers resulted in lower estuarine and nearshore salinities that lasted for several weeks.

Impact of Extreme Disturbances on Suspended Sediment in Western Florida Bay: Implications for Seagrass Resilience

“…Hurricane Irma was a bay-scale disturbance that drastically moved water throughout the estuary, and the combination of the water movement and increased sediment mobility likely led to the expansion of the sediment plume to its largest extent (Liu et al, 2020). The different spatial extent and location at which the two disturbances acted created a spatially explicit gradient in their effects, as seen by the differences in the timing of breakpoints between basins.…”

“…Two basins, Johnson and Rankin, were chosen as focal basins for this study because they are located in the north-central part of the bay affected by the 2015 die-off, and because long long-term seagrass cover monitoring data exists, which are useful to examine recovery trends (Hall et al, 2016; Figure 2). Additionally, the basins were affected by Hurricane Irma, which passed through Florida Bay as a category 4 hurricane in September 2017, disturbing benthic communities and significantly altering the circulation of water in the bay (Liu et al, 2020).…”

A case study of a phytoplankton bloom triggered by a tropical cyclone and cyclonic eddies

“…These two cyclonic eddies were enhanced during and after the passage of Ockhi, which maintained for more than ten days ( Fig 3D). In response to TC passages, different variables may change differently over time and from location to location, with different memories [29].The minimum SSH along the TC track appeared near the center of the cyclonic eddies. The SSH increased from each eddy's interior to its periphery, which was consistent with previous studies about the influence of a cyclonic eddy on the SSH [30].…”

Implementation and comparison of the recent three-dimensional radiation stress theory and vortex-force formalism in an unstructured-grid coastal circulation model

“…The FVCOM is a free surface, 3D, primitive equation model originally developed by Chen et al (2013), which has been extensively applied to coastal oceans, estuaries, lagoons and large lakes (Niu et al, 2015;Jiang and Xia, 2016;Kang et al, 2017;Chen et al, 2019;Liu et al, 2019). It adopts unstructured triangular meshes and sigma coordinates at the horizontal and vertical space, respectively, so that the complicated coastlines and highly variable nearshore bathymetry were well captured.…”