By Allison Kubo Hutchison Noah Friedlander , San Francisco from the Marin Headlands in March 2019 , CC BY-SA 4.0 As you walk the pavement of your city, the buildings rising around you, the impact of a city on the landscape is clear. It changes the skyline and the view. But how does it change the ground below? Does the weight of a city bend the crust below? Thirty years from now it is estimated that 70% of Earth’s population will concentrate into high-density metropolitan regions most of which are coastal. It is evident that our human activities influence the air we breathe but how do the concrete structures influence the land below? Recent research published in the AGU Advances estimated the weight of the San Fransisco Bay region home to about 7.75 million people at 1.6x1012 kg. Author Tom Parsons of the US Geologic Survey calculated the weight by satellite-based building footprints across the Bay area then applied average values for the dead load, the weight of the building its
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