Coastal Residents Face Faster Sea Level RiseMore than half a billion people live in low-lying coastal zones, placing them on the front lines of one of climate change's most serious challenges. The main reason for the difference is land subsidence, the gradual sinking of the ground beneath coastal cities and communities. Some Cities Are Sinking Extremely FastThailand, Bangladesh, Nigeria, Egypt, China, and Indonesia are among the countries experiencing the highest relative sea level rise. In Sweden and Finland, geological uplift is producing a relative decline in sea level along parts of the coast. "In many large coastal cities, groundwater extraction is a major driver of land subsidence.