The Rising sea level This puts all coastal areas of the world at risk of submergence, especially those cities, due to their location and elevation.
According to researchers from Nanyang Technological University (NTU Singapore), The global average rise in sea level is 3.7 millimeters each year. On the other hand, an analysis involving 48 cities showed an average rate of sinking of 16.2 millimeters per year, sometimes reaching 43 millimeters.
Los Cities in danger of sinking They are Tianjin in China; in Ho Chi Minh, Vietnam; Chittagong in Bangladesh; Ahmedabad in India; Jakarta, Indonesia and Yangon, Myanmar are “experiencing significant subsidence at a rate of more than 20 millimeters per year,” the study authors noted.
For its part, for Rio de Janeiro, Brazil, the report warns that by 2030 “nearly two kilometers of the city could be submerged in water if no precautionary measures are taken”.
Meanwhile, 37 more cities have been kept under watch for future studies, one of them City of Buenos AiresIt sank by less than 1 millimeter during the period included in the analysis.
An international team of scientists who participated in the research said the increase in industrial processes such as groundwater, oil and gas extraction, as well as the rapid construction of buildings and other urban infrastructure, may contribute to this vulnerability.
Melting of the Earth’s ice sheets and rising ocean temperatures cause sea level rise. The relatively fastest rates of land subsidence are concentrated in AsiaEspecially in Southeast Asia, adds the study.
How was the study of possible underwater cities?
The team processed satellite images of 48 cities recorded between 2014 and 2020, using a cloud-based processing system called Interferometric Synthetic Aperture Radar (INSAR). The results of the study are published in the journal Science Natural sustainability.
The 48 cities were selected based on two criteria: one A minimum population of five million in 2020And one The maximum distance from the beach is 50 kilometers.
The InSAR system maps Earth’s deformation using radar images of the Earth’s surface, which are collected from orbiting satellites.