Global Mean Sea Level

Global mean sea level has been calculated by satellite measurements since 1993. Several satellites are used in order to determine a mean value.

It is clear, the global mean sea level has been rising steadily since 1993. Currently, the annual rise is calculated to be 3.18 mm a year, which is also taking into account the correction for postglacial rebound, which is -0.3 mm/yr. The calculated error for global mean sea level was determined to be +/- 0.6 mm/yr with a 90% confidence level, according to AVISO.

Keep in mind, sea level does not rise uniformly across the globe, there can be differences anywhere from -10 to 10 mm/year. The image below shows that the greatest sea level rises since 1993 are happening over the western Pacific and parts of the Indian Ocean. Portions of the far north and eastern Pacific have experienced no rise or even a small decrease.

However, when you look at the entire global map there is much more area that is experiencing rising sea levels compared to falling.