Coastal erosion and rising global sea and ocean levels
Among other institutions, scientists from the University of Arizona have documented a dramatic rise in sea levels along the Gulf of Mexico and south-eastern US coasts, progressing since around 2010. According to the National Oceanic and Atmospheric Administration, sea level, measured by tides on Lake Pontchartrain in New Orleans, is more than 20 cm higher than just after Hurricane Katrina in 2006. Rising sea and ocean levels amplify the power of hurricanes. In addition, the wetlands and mangroves that protect people living on the land are shrinking.
Puerto Rico’s governor has declared a state of emergency to combat coastal erosion, which officials blame on climate change. The works and financial investment are intended to compensate for and minimise the loss of land. The funds will cover the cost of moving houses, creating artificial reefs, planting mangrove trees and adding sand to beaches, among other measures. According to the Institute of Coastal Investigation and Planning of Puerto Rico, by July 2018, 40% of local beaches had been affected by erosion and 60% by the accumulation of sand.
In Chellanam on the Arabian Sea, on India’s southwest coast, salt water seeps inland into ponds and wells from which 600 families draw water for drinking, bathing and daily activities. Already 60 years ago, the water was too salty to drink; now, it cannot even be used to clean clothes. Rising sea and ocean levels – at a rate of 1.8 mm per year – extreme storms and excessive water consumption are adding to the region’s salinity problem, which has increased 30% since 1971.