Almost everywhere around the world, sea level has been rising rapidly since 1993. This is because the ocean has absorbed about 90% of the extra heat being added to Earth’s atmosphere from human activities and is warming up, causing water to expand. Also, glaciers and ice sheets are melting at an ever faster rate, adding more water to the seas.
Coastal flooding is one of the most widespread and dangerous impacts of sea level rise. It threatens people’s homes, roads, power plants, drinking water supplies, and other infrastructure necessary for community and economic prosperity. It exposes people to health risks like water-borne diseases, increases in asthma and other respiratory conditions from mold, loss of income, and mental stress and depression from relocation or dealing with a deteriorating home or neighborhood.
Local variations and regional trajectories of sea level rise are also important, as they affect how fast sea levels are rising at the place where you live. Sea levels are rising around the world at a constant rate because of the global warming caused by human activities, but local factors like sinking land or changes in wind and weather patterns can make it seem as though seas are rising faster or slower than they actually are.
These local and regional wiggles (either up or down) in the average daily sea level occur over hours or days. They happen on top of the global average and can have a significant impact on the amount of local flooding and erosion that occurs from tides, storms, and other events.