Publications

We analyzed grain-size distributions (GSDs) from a time-series of sediment samples to evaluate sediment transport following anthropogenic sand-berm emplacement at the northern Chandeleur Islands, Louisiana. End-member analysis (EMA) was applied to compare the end-member (EM) GSD of a known sediment source to GSDs from surrounding environments and characterize the physical redistribution...

Storm surge and large waves combine to erode beaches, cause marsh and coral decay, and inundate low-elevation areas, resulting in hazards to coastal communities and loss of natural resources. The USGS, in collaboration with NOAA, is developing a real-time system to provide ∼ 6-day forecasts of total water levels (TWLs) combining tides, storm surge, and wave runup. TWL is compared with...

No abstract available.

Early coastal dune erosion predictions are essential to avoid potential flood consequences but most dune erosion numerical models are computationally expensive, hence their application in Early Warning Systems is limited. Here, based on a combination of optimally sampled synthetic sea storms with a calibrated and validated XBeach model, we develop a surrogate model capable of producing...

Shoreline variability over timescales ranging from days to decades is examined at NASA-Kennedy Space Center on the Atlantic coast of Florida. Three sources of shoreline position data are utilized to complete this analysis: hourly video-image observations, monthly Real Time Kinematic GPS observations, and historical aerial imagery dating back to 1943. We find that shoreline positions tend...

Satellite derived shorelines are extracted using the Google Earth Engine API for Landsat and Sentinel satellites from 1984 through 2018. These shorelines are evaluated against existing surveys and show satellite-derived breach shorelines are in good agreement with directly-observed shorelines and capture the trend of the Fire Island wilderness breach evolution. Results of this study show...

Climate change is anticipated to exacerbate the extinction risk of species whose persistence is already compromised by habitat loss, invasive species, disease, or other stressors. In coastal areas of the southeastern United States (USA), many imperiled vertebrates are vulnerable to hurricanes, which climate models predict to become more severe in the 21st century. Despite this escalating...

Sea level rise is a fundamental driver of ecosystem change and has the potential to shift the spatial distributions of habitats more rapidly than species can adapt. Rapid sea level rise and associated saltwater intrusion have negative impacts on coastal environments, including loss of habitat for species such as sea turtles and shorebirds. In Florida’s largest wetland, the Everglades...

The Upper Floridan aquifer (UFA) is the principal water source for industrial and public supply in Glynn County, Georgia. Wells in active pumping centers that tap the UFA for industries near the city of Brunswick have created an upward hydraulic-head gradient in the Floridan aquifer system, which has allowed high chloride (saline) groundwater from the Fernandina permeable zone of the...

1. Resource selection is widely appreciated to be context‐dependent and shaped by both biological and abiotic factors. However, few studies have empirically assessed the extent to which selective foraging behaviour is dynamic and varies in response to environmental conditions for free‐ranging animal populations. 2. Here, we assessed the extent that forage selection fluctuated in response...

The Mississippi Delta, located in northwest Mississippi, is an area dense with industrial-level agriculture sustained by groundwater-dependent irrigation supplied by the Mississippi River Valley Alluvial aquifer (alluvial aquifer). The Delta provides agricultural commodities across the United States and around the world. Observed declines in groundwater altitudes and streamflow...

Atrazine is presently one of the most abundantly used herbicides in the United States, and a common contaminant of natural water bodies and drinking waters in high-use areas. Dysregulation of reproductive processes has been demonstrated in atrazine exposed fish, including alteration of key endocrine pathways on hypothalamic-pituitary-gonadal (HPG) axis. However, the potential for...