Istanbul among coastal cities grappling with annual land subsidence: Study

ISTANBUL

A recent study by Nanyang Technological University (NTU) has identified Istanbul as one of 48 coastal cities worldwide sinking due to the dual impacts of climate change-induced sea-level rise and ground subsidence.

The research, reported by the BBC and conducted by the Singapore-based university, highlighted that these vulnerable cities are spread across Asia, Europe and the Americas.

The study states that rising seas, fueled by global warming, and the over-extraction of underground water are accelerating the sinking of these urban areas.

Various parts of Istanbul underwent annual subsidence ranging from 0.01 centimeters to a significant 13.2 centimeters between 2014 and 2020, according to the study.

Notably, Arnavutköy, the district housing the city’s principal airport, emerged as one of the most rapidly subsiding locales.

NASA’s latest assessments indicate a global mean sea-level rise of approximately 0.59 centimeters in 2024 alone.

The NTU dataset was meticulously synthesized with complementary findings from Istanbul Technical University and the Freie Universität Berlin.

Cheryl Tay, the lead investigator of the NTU team, remarked that subsidence is pervasive across numerous urban environments, noting that one of the preeminent drivers is the excessive extraction of groundwater.

“Globally, nearly half of potable and domestic water supplies originate from subterranean aquifers, which are concurrently heavily exploited for agricultural irrigation. Persistent over-extraction undermines the geological substratum, resulting in concomitant surface-level subsidence.”

Upon identifying the subsidence afflicting select districts of Tokyo, Japanese municipal authorities enacted stringent regulatory measures targeting groundwater extraction. This decisive intervention markedly curtailed the progression of land sinking, demonstrating effective mitigation of the underlying causative factors.