LaSII - Land Subsidence International Initiative from UNESCO published the first global subsidence map due to groundwater depletion in SCIENCE. The research, led by Herrera-García from the Geological Survey of Spain, was also developed with the collaboration of Italian researchers Luigi Tosi (IGG-CNR and LaSII), Mauro Rossi (IRPI-CNR), and Pietro Teatini (ICEA-University of Padua and LaSII).

Land subsidence, i.e. the lowering of the earth surface, is a slow and gradual geological hazard that usually affects soft sediments when groundwater is pumped from aquifers. Even though subsidence phenomena have been studied for the past century worldwide, researchers have usually focused on studying and solving the problem locally. The results of this study alerts about a global anthropogenic hazard caused by land subsidence accompanying the depletion of our groundwater resources, which can produce relevant environmental, social and economic impacts. The study revealed that potential subsidence areas threaten 1.2 billion inhabitants and 21% of the major cities worldwide, with 86% of the exposed population living in Asia and estimates that the current economic exposure to potential subsidence amounts to US$8.17 trillion, or 12% of the global gross domestic product. A predictive simulation to 2040 taking into account global change scenarios shown that an estimated 635 million inhabitants will be living in flood prone areas, where land subsidence could increase the flooding risk.

Reference:  Herrera-García G., Ezquerro P., Tomás R., Béjar-Pizarro M., López-Vinielles J., Rossi M., Mateos R.M., Carreón-Freyre D., Lambert J., Teatini P., Cabral-Cano E., Erkens G., Galloway D., Hung W.C., Kakar N., Sneed M., Tosi L., Wang H., Ye S., 2021, Mapping the global threat of land subsidence, Science, Vol. 371, Issue 6524, pp. 34-36, DOI:10.1126/science.abb8549

The paper is available at the link: https://science.sciencemag.org/content/371/6524/34

Author affiliations, Materials/Methods, Supplementary Text, Tables, Figures, and/or References are available at the link:

https://science.sciencemag.org/content/suppl/2020/12/29/371.6524.34.DC1

LaSII-UNESCO web page: https://www.landsubsidence-unesco.org/

For further information, please contact: Luigi Tosi, CNR-IGG (luigi.tosi(at)igg.cnr(dot)it).