Why are oceans rising?

Answer 1

The oceans are rising because global warming is melting the ice caps and glaciers into the ocean and causing it to rise. Also warm water expands and this is also raising sea levels.

Sea level rise is real though at present small and is related to global warming. Sea levels rose by an average of 1.8 mm per year during the 20th century and accelerated to somewhere between 2.9 and 3.4 mm per year for the period 1993 to 2010. The main causes of sea level rise are melting ice sheets and glaciers and thermal expansion of sea water as the oceans warm. Sea level rise is not uniform - the distribution of the rise is affected by variations in the earth's gravitational field and by prevailing winds.

Extremely accurate measurements of sea level are made by satellites.

Answer 2

Sea levels are rising mainly because warm water expands, and the oceans have been warming steadily over the past 40 years. Melting land ice is also adding to rising sea levels.

A common error in climate debate is to focus on short term data instead of looking at long time trends. All sea level graphs (as well as temperature graphs) zig zag up and down. Some years sea levels go down, and the oceans cool, from cyclic events like La Niña (cooling) and El Niño (warming). Other years oceans warm and sea levels rise. Some people try to argue that a downward zag means the sea level rise has stopped, but the long term trend shows that last century sea levels were rising at 2 mm a year, and that since the later years of the 20th Century they have been rising at 3 mm a year.

Answer 3

With the consistent occurrence of global warming these past few years, no wonder the oceans and other bodies of water are increasing in size because of the melting of glaciers and sea ice.