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Sea Level Rise 



Given a time trend in ocean temperature rise, the sea 



level change is estimated as: 



H m +H 

 A H = J dz A a 

 o a 



where a is the specific volume and a a is its change due to 



thermal expansion. For this computation an ocean temperature of 



10°C and salinity of 35 per mille are used. In other words, the 



mixed layer and each of the 62 layers in the thermocline expand to 



a degree that reflects the average pressure, and the rise in 



temperature of the layer (as reflected by the change in density). 



The average global rise in sea level is the output from this 



component of the model. 



Crustal Movements 



Systematic changes in the topography of earth's land or 

 oceans can alter apparent sea level. No changes were assumed 

 however, because global variations occur over a vastly longer 

 time scale than the 120 year period considered here. Clark et al . 

 estimated that long-term isostatic adjustment of the earth's 

 surface has caused a worldwide sea level change of 1 meter per 

 5000 years (2 centimeters per century) ♦ 12 / In certain regions, 

 coastal movements can substantially increase or decrease local 

 sea level rise. However, such trends are likely to balance out 

 worldwide. 



