In an excellent overview of climate adaptation, The Economist writes that climate changes are inevitable, and communities have to adapt. We all (should) by now have a basic understanding that sea level rise will impact coastlines. But, it is the “imapacts” part that we need to understand better.
The other day, I wrote about what salt water can do to building foundations and piers. This is a real impact from sea level rise. In fact, salt from the Mediterranean Sea is encroaching the Nile river delta, ruining soils that nourish date farms and even eating away the foundations of the ancient pyramids. NPR covered it here. Tides ebb and flow into and out of the mouths of rivers that empty into the sea. The freshwater-saltwater transition zones form either deltas or estuaries (quick summary of difference between delta/estuaries here). These zones of brackish/saltier water are expected to expand into areas where people have built infrastructure, such as the footings for bridges, electricity and fiber optic cables buried under ground, storm water pipes, piers and boat moors, etc. These things were not necessarily built to withstand corrosion from salt. To combat the creeping saline water, Urban planners and hazards planners have to act now by conducting infrastructure assessments to locate high risk vulnerabilities.
The Economist expands on tangible impacts by opening up the discussion of human migration.
Ideally, there would be opportunities to move to cities in other countries, too; the larger the region in which people can travel, the easier it is to absorb migrants from struggling areas. This is one reason why adaptation is easier for large countries or integrated regions. Within the EU, Greeks and Italians will be better placed to move to cooler climes than inhabitants of similarly sized countries elsewhere.
What happens to the people who live in cities that cannot deal with very high sea level rise? Mass migrations are expected to occur, and, the article argues, cities are better prepared to absorb population increases. To demonstrate, Hurricane Katrina should come to mind (to be fair, migrations from sea level rise will be very slow, and not occur so spectacularly from one event. Still, people will migrate from flood prone areas in droves, and cities will need to be prepared to absorb a typically poorer demographic.). Estimates range from 100,000 to 300,000 people permanently fled the NOLA region after Katrina.