How Has the Sea Level Risen Over the Years?

how the sea level has risen over the years

Facts and Figures

• Sea-level rise can contaminate water used for drinking and irrigation.
• Up to 216 million people currently live on land that will be below sea level or regular flood levels by 2100.
• Every vertical inch of sea-level rise moves the ocean 50 to 100 inches inland.

how the sea level has risen over the years

Global mean sea level has risen about 8–9 inches (21–24 centimetres) since 1880, with about a third of that coming in just the last two and a half decades.

Global warming is causing global mean sea level to rise in two ways. First, glaciers and ice sheets worldwide are melting and adding water to the ocean. Second, the volume of the ocean is expanding as the water warms. A third, much smaller contributor to sea level rise is a decline in the amount of liquid water on land—aquifers, lakes and reservoirs, rivers, soil moisture. This shift of liquid water from land to ocean is largely due to groundwater pumping.

how the sea level has risen over the years

Sea level is measured by two main methods: tide gauges and satellite altimeters. Tide gauge stations from around the world have measured the daily high and low tides for more than a century, using a variety of manual and automatic sensors. Using data from scores of stations around the world, scientists can calculate a global average and adjust it for seasonal differences. Future sea level rises: As global temperatures continue to warm; sea level will continue to rise. How much it will rise depends mostly on the rate of future carbon dioxide emissions and future global warming. How fast it will rise depends mostly on the rate of glacier and ice sheet melting.