Global Sea Levels
There are two main causes of sea level rise, both related to global warming. First, when water is heated, it expands, i.e., the same amount of water takes up more space. Second, giant ice caps located on Antarctica, Greenland, and other land masses are melting into the world's oceans, increasing the amount of liquid water on the planet. The following image presents data on sea level changes over the past decade.
Source: IPCC Fourth Assessment Report: Climate
Change 2007 Working Group I Report: The Physical
Science Basis, Cambridge University Press Figure 5.14.
These data, taken from satellite observations, represent variations in global average sea level. The graph shows a nearly linear relationship between time and sea level rise. Not only are sea levels increasing, the rate of increase is greater in the 20th century than it was in the 19th, according to the IPCC Fourth Assessment Report.
Last Updated: 08/20/2012