A. Melting sea ice

B. Melting land ice

C. Both have the same effect on global sea level.

Sea level rise is caused primarily by two factors related to global warming: the added water from melting land ice and the expansion of seawater as it warms. Melting sea ice does not contribute nearly as much to ocean water volume because floating ice displaces water in an amount equal to its volume. Some coastal regions and island nations have begun to experience the consequences of sea level rise. Rising seas not only affect dwellings and structures, but fresh water is also affected as rising saltwater begins to contaminate it through "saltwater intrusion."