And Again, the World Just Got A Little More Dangerous

A few weeks ago I wrote here about the links between major weather events (e.g., hurricanes) and earthquakes.  Stopping short of identifying a causal link, scientists have identified a definite correlation between the two.  Now geologists are warning that climate change may make earthquakes in certain vulnerable parts of the world far more dangerous.

Writing specifically about the South Carolina coastal areas surrounding Charleston, where faults already cause frequent tremors (including a big one about 130 years ago), a local paper published an article (also the source of the map above) citing rising sea level as a potential cause for an increase in soil liquefaction danger during an otherwise routine seismic event.  The article goes on to say:

While it’s unclear when the next big quake will hit; the water table looms as a growing concern as the earth warms and seas rise. Previous studies have found the relative depth of groundwater rises along with the sea....

Soil liquefaction serves to topple poorly secured structures, bridges and roads. It also wreaks havoc on important underground infrastructure...  Much of the area’s important infrastructure, including the city’s medical district and the region’s port terminals, sit on artificially filled land that is the most vulnerable. 

Much of that land on the peninsula was filled after the 1886 earthquake.  Recent infrastructure like the Ravenel Bridge has been built to high seismic standards, he said, but they’re embedded in poor soils that could easily liquefy. The bridge also might prove useless if its approach ramps are destroyed.

The article concludes with some recommendations for engineered retrofit of key buildings and structures, but as we've seen in other examples of sea level rise discussed here on this page, the long-term answer may require some tough discussions about relocation.  Whether or not that would happen before or following a seismic event is a subject for another time.