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Wang, P.; Royer, E.L.; Jackson, K., and Gutierrez, S., 2024. Impacts of Hurricane Ian along the low-lying southwest Florida coast (USA) in 2022: Lessons learned. Journal of Coastal Research, 40(5), 827–851. Charlotte (North Carolina), ISSN 0749-0208. Hurricane Ian made landfall in the low-lying, densely populated, and developed southwestern Florida coast on 28 September 2022 as a large and slow-moving category 4 hurricane. Various U.S. federal and state agencies collected a large and comprehensive data set, including pre- and poststorm airborne LIDAR topography, in situ water level and wave measurements at numerous locations before, during, and after the storm, and poststorm high-water marks over a large area. This study reports results from a series of poststorm field investigations including ground observations of beach-dune erosion and deposition, catastrophic damage to various infrastructure, and widespread distribution of non-biodegradable materials washed into the estuary and numerous mangrove islands. Hurricane Ian induced large-scale inundation in low-lying southwest Florida, submerging all the barrier islands bordering Charlotte Harbor estuary, all the islands within the estuary, and up to 5 km into the mainland. Dense tree-type vegetation limited the landward penetration of beach-dune erosion and overwash deposition along the barrier islands. Net sand-volume loss from the beach-dune system ranged 10–25 m3/m and was controlled by the deep submergence of the system during the peak of the storm. The extremely high storm surge of up to 5.2 m above mean sea level generated by Hurricane Ian caused severe damage to the built environments over a large area. High storm waves superimposed on the elevated water level, reaching 1.2 m at the seaward edge of vegetated dunes, contributed to the destruction along the barrier islands. Hurricane Ian distributed a tremendous amount of non-biodegradable artificial debris over a large area and into sensitive natural environments, including numerous mangrove islands, barrier-island interior wetlands, and the estuary waterbody. Measures to prevent materials such as single-use plastics, insulation fibers, and household appliances from being washed into sensitive environments should be a significant part of prestorm preparation. [ABSTRACT FROM AUTHOR]

Jackson, K.; Wang, P.; Pluckhahn, T.J.; Rogers, J.A., and Thompson, V.D., 2023. Stratigraphic framework, paleoenvironments, and Indigenous terraforming of inshore estuarine subbasins in Tampa Bay, Florida, U.S.A. Journal of Coastal Research, 39(5), 779–815. Charlotte (North Carolina), ISSN 0749-0208. Tampa Bay is a karst-controlled estuary system on Florida's central peninsular Gulf of Mexico coast. Although previous work has reconstructed late-Pleistocene environments (ca. 20–11.5 kya) and early marine influence (ca. 8–5.5 kya) in deeper central portions of the bay, the estuarine development of the shallow inshore subbasins remains poorly understood. Across the late Holocene, Indigenous societies terraformed the coastal strand with large volumes of estuarine mollusk shell, and these anthropogenic landforms constitute coastal barriers that partially enclose marginal tidal bayous. This study integrates sediment coring and archaeological excavations to reconstruct the Holocene estuarine evolution of four inshore subbasins within Tampa Bay. This study synthesizes sedimentological, macrofossil, and archaeological data to describe and differentiate seven sedimentary facies and 18 subfacies representing weathered Miocene limestone at the base, overlain by late-Pleistocene freshwater wetland deposits, followed by Holocene estuarine sediments and late-Holocene shell-terraformed settlements. Four stratigraphic cross-sections and >100 radiocarbon assays are utilized to interpret the sequences of inshore estuary development, situate ancient shell-bearing Native settlements within a geologic and paleoenvironmental framework, and resolve elements of mid- and late-Holocene sea-level history. [ABSTRACT FROM AUTHOR]

Brown, M.T.; Dix, N.; Osborne, T.; Castle, A.; Woodward, W.; Hartnett, A.; Dunnigan, S.; Tanner, S., and McGinley, E., 2023. The impacts of a restoration dredging project and storm events on water quality in a northeast Florida barrier island estuary. Journal of Coastal Research, 39(4), 722–739. Charlotte (North Carolina), ISSN 0749-0208. Previous studies in estuarine systems have demonstrated that both dredging projects and storm events can have profound impacts on water quality, particularly increases in nutrients, sediment loading, and shifts in phytoplankton community biomass. This study provided the opportunity to assess the potential relative impacts of a 9-month-long barrier island restoration dredging operation, in comparison to storm events that shortly followed, on water quality in a well-flushed, subtropical NE Florida estuary. Twice-a-month monitoring of turbidity, total suspended solids, chlorophyll-a, and major nutrients (ammonium, nitrate+nitrite, and orthophosphate) was carried out at six sites near the dredging operation area from November 2016 through October 2018. This timeframe sampled the dredging project from January to September 2017 associated with the reopening of the Summer Haven River on the barrier island side of the Matanzas River estuary. In addition, two major storm events, Hurricane Irma in September 2017 and a 5-day nor'easter in October 2017, took place during the water quality monitoring. Although the dredging project did result in notable impacts on total suspended solids and ammonium concentrations, the results highlight how natural storm events can have more significant and lasting impacts on water quality in a well-flushed estuary, particularly with regard to decreases in salinity, input and remineralization of dissolved organic carbon, and increases in dissolved nutrients. [ABSTRACT FROM AUTHOR]

Vickery, C.G.; Wang, P., and Cheng, J., 2022. Natural and anthropogenic factors controlling circulation at the terminus of a seagrass-covered estuary, Fort DeSoto Bay, West-Central Florida. Journal of Coastal Research, 38(4), 681–698. Coconut Creek (Florida), ISSN 0749-0208. Causeway construction and channel dredging are common engineering activities in shallow estuaries and can significantly alter natural circulation patterns. Bridges are often installed on causeways to improve circulation. This study examines the influence of dredged channels, causeways, and bridges on circulation patterns within a shallow estuary with dense seagrass beds using a calibrated and verified numerical model. For the case of Fort DeSoto Bay in west-central Florida, the causeways disrupted the natural east-west flow and reduced current velocities within the seagrass beds in the southern terminus portion of the estuary by up to 76%. The tidal bridges increased velocity in the stagnant areas by up to 226%. Up to 26% of the tidal prism in the lower half of the bay passes through the bridges during a spring flood-tidal cycle. Thus, the bridges significantly improved tidal flushing between the estuarine cells divided by causeways. The unvegetated dredged channels serve as efficient conduits that facilitate penetration of tidal currents into the southern and terminus of the bay, leading to significantly higher current velocity in the channels and corresponding reduced velocity over the adjacent seagrass beds. The channels allow for improved tidal flushing within the otherwise stagnant southern terminus of the bay and therefore can be designed for the purpose of improving circulation. [ABSTRACT FROM AUTHOR]

Schiariti, J.P. and Salmon, M., 2022. Impact of Sargassum accumulations on loggerhead (Caretta caretta) hatchling recruitment in SE Florida, U.S.A. Journal of Coastal Research, 38(4), 725–734. Coconut Creek (Florida), ISSN 0749-0208. Hatchling loggerhead turtles emerge from subsurface nests on oceanic beaches at night, then crawl toward and enter the sea. Recently, increases in a floating algae (Sargassum spp.) have been reported in the mid-Atlantic and Caribbean, resulting in large accumulation on Florida's beaches. The purpose of this study was to determine if, during the 2020 nesting season, these accumulations acted as a barrier that prevented the hatchlings from crawling to the sea. Seasonal changes in Sargassum density were recorded to determine when, and under what circumstances, hatchlings could cross the accumulated wrack. There was a significant overlap between when Sargassum accumulations peaked and when the turtles emerged, with the result that during the 2020 nesting season the number of hatchlings that entered the ocean was reduced by an estimated 22%. These results suggest that algal accumulations represent a significant threat that could potentially impede the recovery of loggerhead populations that currently are either threatened or endangered, worldwide. [ABSTRACT FROM AUTHOR]

Cheng, J. and Wang, P., 2022. Factors controlling storm-induced morphology changes at an erosional hot spot on a nourished beach, Sand Key barrier island, west-central Florida. Journal of Coastal Research, 38(4), 750–765. Coconut Creek (Florida), ISSN 0749-0208. Beach nourishment has become the dominant sandy shore protection method over the past 40 years. The performance of nourished beaches and therefore the design of renourishment projects are significantly controlled by the presence of erosional hot spots and storm impacts. Based on 5.5-year bimonthly beach profile surveys, along a nourished beach spanning an erosional hot spot, this study examines the hydrodynamic conditions of extratropical (winter) and tropical (summer) storms that cause significant morphology changes. The sand volume loss above the short-term closure depth averaged along the 1.8-km stretch erosional hot spot was 178 m3/m over the 5.5 years after the nourishment. A large portion of this volume loss was caused by several extratropical storms and Hurricane Irma in 2017, when the high, northerly approaching waves were associated with a depressed water level. The northerly approaching waves induced a large longshore sediment transport gradient along the generally north-south trending coast due to wave refraction over a nearby ebb tidal delta. The energetic Hurricane Irma induced a large negative surge and also transported sediment seaward beyond the short-term closure depth. On the other hand, during the passages of typical tropical storms, the southerly approaching waves superimposed on elevated water levels caused substantial beach volume loss above the mean sea level. The eroded sediment deposited on the nearshore sandbar, resulting in conserved sand volume above the short-term closure depth. Understanding the different beach response to extratropical and tropical storms would benefit beach management, especially under the circumstance of increasing storm activities due to climate change. [ABSTRACT FROM AUTHOR]

Fenster, M.S.; Hughes, C.P., and Stutz, M.L., 2022. A survey of global mixed-energy and wave-dominated barrier island distribution and development. Journal of Coastal Research, 38(4), 795–806. Coconut Creek (Florida), ISSN 0749-0208. This study quantifies the length, percentage, and type of development found on global mixed-energy and wave-dominated coastal plain and deltaic barrier islands. Google Earth photographic imagery from 2015–2017 was used to measure the lengths of individual islands, identify infrastructure types 300 m landward of the shoreline, and measure the alongshore extent of each island's land uses. The United States Geological Survey's land-use classification scheme enabled categorization and quantification of predominant structure types. The results from this study showed that, of the 1444 mixed-energy and wave-dominated barrier islands located within 53 countries around the world: (1) 832 (approximately 59%) of those barriers islands have some type of development; (2) approximately 16% of the total length of shorelines (approximately 1,793 km/11,249 km) are developed; (3) wave-dominated barriers (approximately 17%) are more developed than mixed-energy (approximately 14%) barriers; (4) coastal plain (approximately 21%) settings have double the development than deltaic settings; (5) the U.S. contains approximately 66% of all developed global barrier island shorelines and the highest percent development of mixed-energy (New Jersey approximately 67%) and wave-dominated (Florida approximately 62%) coastal plain barrier islands in the world; and (6) high-density, residential dwellings dominate development type and comprise an average 14% of the world's barrier island shorelines. Finally, development percentage and/or land use type do not appear to depend on or correlate with hydrodynamic or geologic setting and coastal processes and geology do not influence development type. Instead, site specific or regional factors most likely dictate the percentage and type of development. [ABSTRACT FROM AUTHOR]

Campbell-Martínez, G.E.; Thetford, M., and Miller, D., 2022. Germination response of three florida panhandle coastal dune plants to salinity. Journal of Coastal Research, 38(3), 585–591. Coconut Creek (Florida), ISSN 0749-0208. Coastal dunes and their ecosystem services are threatened by human pressures warranting active restoration. Understanding dune plant germination responses to salinity is important when considering plant species and direct seeding locations for coastal dune restoration projects. The germination response of three Florida panhandle native coastal dune plant species to various salinity concentrations (0%, 0.25%, 0.50%, 0.75%, and 1% weight per volume) were tested. Species included were coastalplain honeycombhead (Balduina angustifolia (Pursh)B.L.Rob.), coastalsand frostweed (Crocanthemum arenicola (Chapm.)Barnhart), and squareflower (Paronychia erecta (Chapm.)Shinners). Seeds were germinated within germination boxes, placed in growth chambers under species-specific temperatures with a daily 12-hour photoperiod, and monitored weekly for 4 weeks. Germination responses to salinity were species-specific. Coastalplain honeycombhead had intermediate salt tolerance (highest germination at 0%–0.50% salinity), coastalsand frostweed was the least salt tolerant (highest germination at 0%–0.25% salinity), and squareflower was the most salt tolerant species in respect to germination (high germination across all salinities). Germination was delayed for all species at the highest salinity concentrations (0.75%–1%). However, for all three species, at least one-third of all seeds (>39%) at all salinity concentrations germinated by week 4. Results suggest germination for seeds of these species is possible in saline conditions documented within coastal areas before and after hurricane overwash. Future dune restoration studies for these species should test direct seeding of these plants under field conditions. [ABSTRACT FROM AUTHOR]