Page 52: of Marine Technology Magazine (March 2023)

CASE STUDY

D S EAD EA

C OASTAL

E ROSION

R

ESEARCH oastal erosion is reshaping our world, literally, coastal movements of sediments in the Dead Sea, a hypersa- threating homes and business. By taking advan- line lake located between Israel, Jordan and the West Bank. tage of the unique conditions in the Dead Sea The Dead Sea is primarily fed by the Jordan River and does and leveraging modern ADCP technology, sci- not drain or discharge to the ocean, making it a terminal lake.

Centists in Israel are exploring how wind-driven Sediments from the Jordan River and other channels make waves and currents shape the coastlines and transport sedi- their way to the Dead Sea through a variety of sediment trans- ments along shores. port processes.

This research could contribute to improving the design of “Fluvial channels supply unsorted sediment to the lake dur- boulder-based breakwaters, placed offshore to absorb wave ing winter storms,” says Eyal. energy and mitigate erosion across the world. During these storms, waves transport sediments from the

Every year, around 24 percent of the world’s sandy shoreline channel mouth along the shore, creating berms – beach ridges erodes away,1 causing signi? cant ? nancial loss from damage that extend along the shore.

to property and infrastructure. With around 40 percent of the During the dryer and hotter summer months, the lake level global population living within 100 km of the coast, erosion drops about 1 m.

presents a real and immediate challenge. Coastal erosion is a According to Eyal, because of the dramatic seasonal drop costly affair. In the USA, for example, coastal erosion causes in water level, these berms are unique to each winter season, an estimated $500m in property loss and damage every year. creating an environment where sediments from each storm are

Cutting-edge environmental research in Israel is taking ad- preserved separately. This is unlike other areas where the wa- vantage of new technologies and the unique environment of ter level is relatively stable from one season to the next. the Dead Sea to better understand the processes behind coastal erosion and sediment transport. “Understanding coastal ero-

COASTAL EROSION & ATMOSPHERIC sion and the transport and sorting of coarse sediments along

AND OCEANOGRAPHIC PROCESSES shores is highly important for assessing coastal stability,” says To understand the role different atmospheric and oceano-

Haggai Eyal, a PhD candidate at the Hebrew University of graphic processes play in coastal erosion and apply that

Jerusalem. He is supervised by Professor Nadav Lensky from knowledge to other parts of the world, real-world oceano- the Geological Survey of Israel and Professor Yehouda Enzel graphic measurements are necessary. from the Hebrew University of Jerusalem. “This is where the science of coastal erosion is challenging, speci? cally where waves break,” says Lensky. “You need the

CAPTURING SEDIMENT MOVEMENTS wind measured properly, which is easy enough, but then you

DURING WINTER STORMS need to measure currents and waves, which is very hard to

Eyal’s PhD focuses on the ? uvial (relating to rivers) and achieve.” 52 March/April 2023

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