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Asbury Sallenger

Publications and source records attributed to Asbury Sallenger.

6 recordsLinked to original sources
USGS2011

Coastal sedimentary research examines critical issues of national and global priority

An international conference was held recently in Honolulu, Hawaii, to examine and plan for coastal sedimentary research in the United States and globally. Participants agreed that sedimentary coastal environments constitute a critical national and global resource that suffers widespread degradation due to human impacts. Moreover, human population growth and inappropriate development in the coastal zone are escalating public asset losses due to coastal hazards and placing large numbers of communities at growing risk (Figure 1).

Hawai'i↗
USGS2003

Tropical Storm Isidore and Hurricane Lili: Louisiana barrier shoreline response, preliminary results

In a cooperative effort between the U.S. Geological Survey, National Aeronautics and Space Administration, University of New Orleans, and Louisiana's Department of Natural Resources, Louisiana's barrier islands were surveyed with airborne topographic lidar and oblique aerialphotography both before and after the impacts of 2002's Tropical Storm Isidore and Hurricane Lili. The surveys were compared to quantify the magnitudes and patterns of erosion and accretion in both natural areas and areas that had been subjected to major restoration. Wave runup exceeded the elevation of the entire Isles Dernieres barrier chain creating overwash deposits that, in places, were driven landward ~ 300 m. This response was not as severe as observed during Hurricane Andrew in 1992 when the Isles Dernieres were completely and continuously inundated and sand bodies were driven landward on the order of 1 km. Based on a comparison of surveys before and after the combined impacts of Lili and Isidore, the largest shoreline change occurred at the east end of East Island and reached ~ 130 m of erosion.

Louisiana↗
USGS1995

How much velocity information is necessary to predict sediment suspension in the surf zone?

Instantaneous horizontal water velocity, or velocity to a power, does not contain enough information to predict suspension in the surf zone. Unlike steady uniform flow, more one than one velocity is necessary to parameterize pick-up and mixing of sediment into the water column. Using a velocity history improves predictions of suspension by more carefully specifying flow conditions (including accelerations and changes in accelerations) responsible for suspension. Suspension in the future is better predicted than suspension at the same instant as velocity measurements. Incorporating such a lag between velocity and concentration improved predictions, with optimum lag time increasing with elevation above the sea bed. These lags are largely due to the time for an observed flow event to effect the bed and mix sediment upward.

Conference Paper↗