Coastal Erosion Costs $500M in Property Loss Each Year

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coastal erosion (Credit: Hebrew University of Jerusalem)

Every year, around 24% of the world’s shoreline is eroding away, causing significant financial loss from damage to property and infrastructure. With around 40% of the global population living within 100 km of the coast, erosion presents a real and immediate challenge.

Coastal erosion is a costly affair. In the US, for example, coastal erosion causes an estimated $500 million in property loss and damage every year. New environmental research in Israel is taking advantage of new technologies in conjunction with the unique environment of the Dead Sea to better understand the processes behind coastal erosion and sediment transport.

“Understanding coastal erosion and the transport and sorting of coarse sediments along shores is highly important for assessing coastal stability,” says Haggai Eyal, a Ph.D. candidate at the Hebrew University of Jerusalem.

The Dead Sea is primarily fed by the Jordan River and does not drain or discharge to the ocean, making it a terminal lake. Sediments from the Jordan River and other channels make their way to the Dead Sea through a variety of sediment transport processes.

During winter storms, waves transport sediments from the channel mouth along the shore, creating berms – beach ridges that extend along the shore. Then, during the drier and hotter summer months, the lake level drops about 1 m.

The researchers used acoustic instrumentation (ADCPs) from Nortek to provide crucial quantitative measurements of the currents throughout the water column and directional waves simultaneously. The measurements from the study revealed some key insights about the processes that dictate transport in the Dead Sea.

The study was published in Geophysical Research Letters in collaboration with researchers from the University of California in the USA and Technische Universität Braunschweig in Germany. This research offers insights into sediment transport processes beyond the Dead Sea. Using the observations from the study, the researchers demonstrated how sediment sorting is directly related to the wave climate. They developed a new model for quantifying the wave height needed to move a given mass of gravel and formulated how the distribution of wave heights during a storm sorts gravel along the shore.

This information is helpful in designing boulder-based breakwaters, structures built from boulders placed offshore intended to absorb wave energy.

In the US, Pacific Northwest National Laboratory (PNNL) researchers are doing similar studies while working to power batteries with energy from ocean waves through the development of a new cylindrical triboelectric nanogenerator (TENG)—a small powerhouse that converts wave energy into electricity to power devices at sea. Larger versions of this generator could be used to power ocean observation and communications systems, including acoustic and satellite telemetry. 

Without power, ocean sensors can’t collect critical wave and weather data, which results in safety concerns for coastal communities that rely on accurate maritime weather information. 

Environment + Energy Leader