A new study indicates that Alexandria, Egypt, is facing a dramatic increase in building collapses due to rising sea levels and coastal erosion, with incidents rising from one yearly to forty. This escalation threatens the city’s historical structures and infrastructure, prompting researchers to propose protective measures such as sand dunes and vegetation barriers. Approximately 7,000 buildings are at risk as sea conditions worsen, highlighting a significant issue for urban coastal areas worldwide.
Recent research reveals that Alexandria, Egypt, the birthplace of Cleopatra, is currently witnessing a significant rise in building collapses linked to climate change, specifically coastal erosion and increasing sea levels. Once infrequent, incidents of building collapses in this ancient port city have skyrocketed from approximately one per year to an alarming average of 40 annually over the past decade. This alarming trend poses a threat to Alexandria’s rich historical heritage as rising seas and seawater penetration undermine the foundations of coastal buildings.
Founded over 2,000 years ago by Alexander the Great, Alexandria is one of the oldest and most populated cities in Africa, currently home to around six million residents. Surrounded by both modern structures and ancient landmarks, the city is especially susceptible to the impacts of climate change. Sara Fouad, the study’s lead author from the Technical University of Munich, notes that the ongoing rising seas and severe storms are rapidly destroying centuries of human achievements.
The researchers undertook an extensive analysis of Alexandria’s shoreline changes, employing various techniques to catalog the conditions of collapsed structures. By developing a digital map that details the locations and conditions of collapsed buildings from 2001 to 2021, they supplemented their investigations with satellite images and historical maps from 1887, 1959, and 2001. This comparative study revealed that the city’s coastline has significantly retreated inland over two decades, resulting in elevated groundwater levels that jeopardize the stability of nearby buildings.
In addition, scientists examined isotopic variations in the soil to assess the consequences of seawater intrusion. “Seawater intrusion erodes foundations and weakens the soil,” said Ibrahim H. Saleh, a soil radiation scientist at Alexandria University. The study indicates that even minor sea level increases, only a few centimeters high, can lead to tragic collapses. Approximately 7,000 older structures in Alexandria are now at considerable risk.
In recent incidents, such as a building collapse in Wardiyan that claimed four lives and a 14-story structure that fell two years prior, researchers have identified groundwater damage as a possible culprit. Fouad expressed concern over the effects of encroaching groundwater on the city’s infrastructure. To protect against these threats, researchers suggest implementing sand dunes and vegetation barriers along the shoreline to mitigate seawater intrusion and preserve building foundations.
This sustainable and cost-effective strategy could benefit urban coastal areas worldwide. Steffen Nijhuis from Delft University of Technology remarked on the global applicability of their proposed solutions. Notably, Alexandria is not singular in confronting climate threats; many Mediterranean coastal cities, along with parts of the California coastline, face similar vulnerabilities. Essam Heggy, a study author, emphasizes the urgency of addressing these issues, stating, “Our study challenges the common misconception that we’ll only need to worry when sea levels rise by a meter.”
The situation in Alexandria highlights the critical challenges posed by climate change to urban coastal environments. The rise in building collapses underscores the urgent need for protective measures against rising sea levels and coastal erosion. Alexandria’s historical architecture, vulnerable to these environmental changes, requires immediate intervention to safeguard its heritage. Furthermore, the proposed solutions could serve as effective models for other global coastal cities facing similar threats.
Original Source: www.cnn.com
