From Envirowiki

Sea level rise is the average height of the world's oceans rising, and covering more land. Current seal level rise may appear small (it is often measured in centimetres per decade), however coastal land is often very nearly flat, and a ten centimetre rise vertically can mean horizontal encroachment of many meters. This can lead to coastal erosion, soil salination, and more dangerous high tides.

Contents 1 Causes 2 Predictions 3 Impacts 4 References

[edit] Causes

Climate change is thought to be a key factor in current sea level rise, the two primary driving factors being glacial melting, including the parts of the polar ice caps which are on land (See West Antarctic Ice shelf), as well as oceanic thermal expansion (two more minor factors are dams and irrigation practices on land, and sea bed expansion since the last ice age^[1]). The latter of these is more constant and predictable, and currently has a larger impact, the former has a possibility of being much larger and more sudden, but it's very unpredictable.

[edit] Predictions

Will Steffen from the ANU says that the sea-level could rise by 4 meters this century^[2]. Other predictions are from a minimum of 80cm to a maximum of a little over 2m, and "suggest that 80 cm should be the 'default' value"^[3]

Other predictions include an additional 7 meters if the Greenland icecap melts, and another 6-7 meters for the West Antarctic ice shelf^{[reference needed]}, these figures refer to periods of hundred or perhaps thousands of years.

[edit] Impacts

Sea level rise is already impacting a number of low-lying pacific atolls, including the Cartaret islands Tuvalu, as well as a number of delta regions around the world, such as the Sundarbans world heritage area.

1 meter of sea level rise (slightly above the average estimate of sea level rise by 2100) would affect 145 million people, and cause almost US$1 trillion of damage, given today's population and economy^[4].

[edit] References

1. ↑ Schmidt, Gavin A. (2008-06-19). "Ocean heat content revisions". RealClimate. Retrieved on 2008-06-24.
2. ↑ "Sea levels could rise 4m this century: climate expert" (item) (2008). Retrieved on 2008-08-20.
3. ↑ "How much will sea level rise?". RealClimate (2008-09-04). Retrieved on 2008-09-29.
4. ↑ Ahlenius, Hugo (2007-06). "Population, area and economy affected by a 1 m sea level rise (global and regional estimates, based on today's situation)". UNEP/GRID-Arendal. Retrieved on 2008-09-29.