The History of Rising Seas

Since 1933 the UK's National Oceanography Centre has been maintaining the Permanent Service for Mean Sea Level (PSMSL), a repository for tide heights around the world. The PSMSL provides an invaluable guide to long-term sea level change across the globe.

CORRECTIV has used the PSMSL data to map out the history of sea levels around the world since 1985. Steigende Meere includes an animated map which shows recorded tide gauge data across the globe for every year since 1985. The article accompanying the map is in German but the map itself is easy to understand. The red spikes show the size of rising seal levels and the green spikes show the size of recorded falls in the sea level.

CORRECTIV reports that the oceans absorb 80 percent of the extra heat from global warming. Warmer water expands and therefore needs more space. The result is rising sea levels. Global warming also causes glaciers to melt, which also contributes to rising seas. In some places, such as in southern Scandinavia, the melting glaciers put pressure on the land masses, so they lift up. Therefore global warming can actually cause rising land levels on some coastlines.


This isn't the only mapped visualization of the historical Permanent Service of Mean Sea Level data by CORRECTIV. CORRECTIV has also mapped the records from 500 of the over 2,000 PSMSL gauges to provide an insight into how sea levels have changed in the last century and how they might change in the future.

Using CORRECTIV's Rising Seas map you can select any of the 500 mapped meters anywhere in the world. When you click on a meter you can view a graph of the meter's measurements since 1933. The map sidebar also provides an overview of how sea level has changed at this location since the measurements began. As well as measurements from the 500 meter readings the Rising Seas map includes an overlay which shows you coastal areas which are within 10 meters of sea level and therefore most at risk from rising sea levels.