Sea level rise is not a new phenomenon. For much of the 20th century, the global mean sea level has been inching upward – about 0,05 inches (1,4 millimeters) per year, according to the United Nations‘ Intergovernmental Panel on Climate Change. Global mean sea level is an average of all the seas covering the Earth. But during the last two decades, the rate has more than doubled. From 2005 to 2015, sea levels rose by 0,1 inches (3,6 mm) per year.

Many places are experiencing a rise as the global mean rises, but in a few places sea level is falling, said Jacky Austermann, an assistant professor of Earth and environmental sciences at Columbia University’s Lamont­‑Doherty Earth Observatory in New York. „There’s not a place that’s immune from sea level change,“ Austermann told Live Science.

Source: Livescience.com, 2020, „How will sea levels change with climate change?“ (https://www.livescience.com/where­‑sea­‑levels­‑are­‑changing.html)

What is a global mean sea level?