A long‐term change in the relative level of land and sea, which can be caused by isostatic adjustment of the land (as a result of tectonic forces), and/or by eustatic change (change in the volume of water that is stored in the oceans). Geological evidence suggests that during the height of the last glaciation (about 18 000 years ago) sea level was between 110 metres and 140 metres lower than it is today, and large areas of the continental shelves were dry land. Sea level has risen through the post‐glacial period (the so‐called Flandriantransgression), rapidly at first, but levelling off about 5000 to 6000 years ago. It has remained relatively close to its present position over the last 5000 to 6000 years. Global warming has caused a global rise in sea level of between 15 and 20 centimetres over the last century; roughly 2–5 centimetres of the rise has been caused by melting of glaciers and ice caps, and another 2–7 centimetres has resulted from the expansion of ocean waters as they warm.
Subjects: Environmental Science.