Understanding the Phenomenon
Before I delve into the list of cities, it’s crucial to understand why cities sink. The primary reason behind sinking cities today is anthropogenic changes to soil-bearing capacity following heavy loading and excessive groundwater extraction (or oil and gas). Land subsidence can also have natural causes like tectonics, glacial isostatic adjustments, and natural sediment compaction.
The Sinking Cities
Jakarta is the fastest-sinking city in the world. Large parts of the city have settled two to four meters since the 1970s. The city is sinking due to excessive groundwater pumping, which could result in it being underwater by 2050.
Houston, Texas, USA
Houston has severe subsidence problems from groundwater pumping and oil and gas extraction. By 1979, almost 10 feet of subsidence occurred in the region. Houston’s continuous sinking makes it vulnerable to natural disasters such as Hurricane Harvey, which affected thousands of people.
Venice is sinking at a rate of 0.08 inches every year. The city is built on wooden piles driven into the marshy ground, which is not the most stable foundation. Over time, the town’s weight has caused the ground to compress, leading to subsidence.
New Orleans, Louisiana, USA
New Orleans is sinking at a rate of 2 inches per year. Both human and environmental factors are to blame for New Orleans’ sinking land. The city is built on soft, silt-heavy soil, and oil and gas extraction has also contributed to the subsidence.
Bangkok is sinking more than 1 centimetre yearly and may be below sea level by 2030. The city is built on a swamp, and the excessive groundwater pumping has caused the land to sink.
Miami, Florida, USA
It’s worth mentioning Miami, Florida. Miami is experiencing floods, contaminated drinking water, and significant damage to homes and roads. However, it’s important to note that the city’s sinking is primarily due to its location and human activities, not climate change. It does not build upon bedrock, mainly coral that is eroding.
It’s important to clarify a common misconception: climate change is not the primary driver of these cities’ sinking. While it’s true that climate change can contribute to rising sea levels, the primary cause of these cities’ sinking is their location and human activities, such as excessive groundwater extraction and heavy loading on the soil.
Research from the U.S. Geological Survey indicates that various factors, including temperature, salinity, and ocean water volume, influence sea level changes. However, the sinking of cities like Jakarta, Houston, Venice, New Orleans, Bangkok, and Miami is primarily due to their location and human activities, not sea level rise caused by climate change.