A new study from the USC Viterbi School of Engineering researchers, along with researchers from the Institute de Physique du Globe de Paris at the University of Paris Cité, has found that the increase in soil erosion in coastal areas due to desertification is worsening flood impacts on Middle Eastern and North African port cities.
Over the past decade, the North African Sahara, an area larger than the continental United States, has faced a dangerous combination of conditions; increasingly arid conditions which are interrupted by intense, coastal rainstorms.
The source of such changes are as follows: increasing desertification has led to intensified droughts, and rainstorms in the region have increased in frequency due to the rising seawater temperature in the Eastern Mediterranean because of global warming.
A year ago, in the Fall of 2023, Storm Daniel also known as “Medicane Daniel” struck the eastern coast of Libya, causing unprecedented flash floods with a death toll of more than 11,300 people and large-scale infrastructure damage. (It has been suggested by the Yale Climate Connections that flash floods of this nature have not been observed on the continent in over 100 years.)
They suggest that sediment loading, resulting from surface erosion, increased the density of flowing water and exacerbated the catastrophic impact of the flash floods in the coastal cities of Derna and Susah, where 66% of Derna’s, and 48% of Susah’s urban surfaces experienced moderate-to-high damages.
The researchers demonstrated that the flow within the streams was heavily loaded and thickened with eroded soils which increased the flow’s destructive nature. This, in turn, contributed to the failure of two dams that were supposed to protect the city and residents of Derna.