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LIDAR mapping is now making a huge contribution to coastal geologists studying how beaches and dunes change in time and space. LIDAR is used for light detection and ranging and this system sends out pulses of laser energy to measure the distance to a surface that reflects the energy.

Taylor, E.B.; Gibeaut, J.C.; Yoskowitz, D.W., and Starek, M.J., 2015. Assessment and monetary valuation of the storm protection function of beaches and foredunes on the Texas coast. Beaches and dunes dampen wave energy and protect against storm surge. This protection is not uniform and varies according to geomorphic characteristics along the coast. Barrier island communities should identify the protection afforded by beaches and dunes to better assess their vulnerability and inform decision making regarding management alternatives. Our study presents a classification identifying a theoretical level of protection that beaches and foredunes could provide against overwash resulting from a tropical storm or hurricane along Mustang and North Padre Islands, Texas. In addition, a monetary valuation of this protective function is estimated at a site level. The theoretical level of storm protection was determined by assessing the response of representative beach-dune profiles to a set of synthetic storms and identifying the storm level at which profiles were overwashed. A monetary value was then assigned to the storm protection function of beach-dune profiles using a replacement cost approach. The level of protection afforded by beaches and foredunes varies across the islands. Some areas are more vulnerable to overwash and inundation during low-intensity storms. About 50% of the assessed beach-dune profiles provide overwash protection against at least a 100-year storm. Areas with the highest protection levels (100 and 200 y) share the following characteristics: (1) they have high dunes (>4 m in elevation), (2) they are in largely undeveloped areas or where buildings are at least 150 to 200 m landward of the line of vegetation, and (3) they generally have a wider beach-foredune complex width. The total annual value of the storm protection function of beaches and foredunes is estimated to be $141.4 million (USD 2013, replacement cost equivalent). [ABSTRACT FROM AUTHOR]

Barrier islands provide a host of critical ecosystem services to heavily populated coastal regions of the world, yet they are quite vulnerable to ongoing sea level rise and a potential increase in the frequency and intensity of oceanic storms. These islands are being degraded at an alarming rate, in part because of anthropogenic attempts at stabilization. In this article, we outline a possible sustainability strategy that incorporates the natural degree of substrate instability on these sedimentary landscapes. We recommend placing the focus for managing barrier islands on maintaining ecosystem function and process development rather than emphasizing barrier islands as structural impediments to wave and storm energy. [ABSTRACT FROM AUTHOR]

The development of coastal sediment budgets and models for sediment transport and shoreline change require bathymetric surveys with vertical resolution and accuracy of 5 cm or better. Horizontal resolution and accuracy need to be at least 10 cm to quantify bedforms and bars.Sleds are probably the most accurate, widely used system for nearshore surveys, but their contact with the bottom limits their speed, spatial resolution. and ability to operate in many situations. Boat-based echo sounder surveys can achieve a higher spatial resolution and can operate where sleds cannot, but waves, tides, and other water-levelfluctuations as well as boat dynamics and variations in the speed ofsound in water can greatly limit their accuracy. Problems related toa survey sled's contact with the bottom cannot be overcome; therefore, echo sounder surveys must be improved. The newly developed high-accuracy, high-resolution bathymetric surveying system (HARBSS) is designed to overcome the confounding effects of changing vessel draft, waves, and tides on depth soundings and to eliminate the need for measuring and modeling water level for a particular survey. The system combines Global Positioning System (GPS) receivers, an electronic motionsensor, a digital-gyro compass, a digital-analog echo sounder, a conductivity. temperature-depth probe (CTD), a computer, and custom software. The GPS antenna, compass, and motion sensor are aligned with the echo sounder's transducer. Using a bias-free phase solution from the GPS data (X,Y,Z accuracy of better than 1 cm), attitude informationfrom the motion sensor, and heading information from the compass, the position and aim of the transducer is determined for each sounding.The CTD provides data to calculate the speed of sound. Using the above data, the sounding depths and horizontal locations of sounding points are corrected in X, Y, and Z with respect to an Earth-centered ellipsoid. In constant and uniform speed-of-sound conditions, HARBSS can provi [ABSTRACT FROM AUTHOR]