Roughly speaking, sea level rise is currently estimated at 3.7 mm per year – a number that varies from region to region in the world. By comparison, the authors of this new study estimate that between 2014 and 2020, the average rate of land ‘sinking’ or subsidence ranged from 1.1 mm for the least vulnerable cities to 16.2 mm – and some of the cities most at risk even in neighborhoods over 20 or even 30 mm per year during this period. Among them are Tianjin in China and Ahmedabad in India. Not far from Ho Chi Minh, Vietnam or Jakarta, Indonesia. But overall, 44 of the 48 cities surveyed exceeded the 3.7 mm limit.
Where the results of these researchers came, Posted on September 12 in Nature Sustainability, disputed, in the choice of areas to be taken into account. they chose the entire territory of the respective towns; Others have recommended To count only the part located a short distance from the beach.
anyways, the reasons From this “inclusion” is the same everywhere: pumping ground waterextraction of oil or gas, compression of sediments under the weight of the largest buildings.
In the language of geologists, this process is called drop. This means that in the absence of sufficiently high flood barriers, or rainwater drainage systems more efficient than they are today, Entire neighborhoods will increasingly become underwater during the next major storms.
Photo: Tianjin, China / Wikipedia Commons
