By Katy Daigle and Carolyn Gramling
In the 20th century, ocean levels rose by a global average of about 14 centimeters, mainly due to melting ice and warming waters. Some coastal areas saw more sea level rise than others. Here’s why:
Expanding seawater
As water heats up, its molecules take up more space, contributing to global sea level rise. Local weather systems can influence that effect. In 2017 scientists reported in Geophysical Research Letters that weakening monsoon winds have resulted in hotter surface ocean temperatures in the northern Indian Ocean, causing local sea level rise. Those weaker winds curtailed ocean circulation that normally brings cooler water up from the deep. Surface waters in the Arabian Sea, for example, got warmer than usual and expanded, raising sea levels near the island nation of Maldives at a slightly faster rate than the global average.