Controls on sea level vary widely in both temporal and geographic scale:
1) tectono-eustatic; first order control on basin shape. (long term)
2) sedimento-eustatic; erosion of mountains, etc. (long term)
3) juvenile H2O formation; via vulcanism. (long term)
4) glacial-interglacial. (shorter term)
5) glacial-isostatic; glacial rebound, e.g. Norway (shorter term)
6) hydro-isostatic; loading with water rather than ice (shorter term)
Thermal expansion is a potential source of short-term sea level rise, but not the only one. Melting of ice currently floating in the North Atlantic may have indirect effects on sea level (due to complex ocean-atmosphere interactions), but will not directly cause sea level to change (principle of isostasy).
Now the melting of the Antarctic ice sheet is another matter...
Do a google search on "NADW formation" and you'll find out why Europe's climate is moderate.
The general idea is: warm salty water delivered to the North Atlantic (ie, Gulf Stream) sinks; salinity is directly proportionate to density. As the denser water sinks, it cools, exchanging heat with the atmosphere. An additional factor that influences NADW formation is sea ice formation. When sea ice forms, most of the solutes are left behind, so salinity increases in the North Atlantic with increased sea ice formation.
Any climate changes that decrease salinity will have a negative effect on ocean-atmosphere heat exchange. So, paradoxically, as atmospheric temps rise, less sea ice forms and evaporation increases resulting in less salinity differential and thus decreased NADW formation. Instant European ice age.
This has happened before as the northern hemisphere exited the previous ice age. Meltwater from retreating glaciers was dumped into the North Atlantic, decreasing salinities and shutting down NADW formation. Instant European ice age. This is referred to as the Younger-Dryas event, and it lasted roughly 500 years.
Slashdot Mirror
Controls on sea level vary widely in both temporal and geographic scale:
1) tectono-eustatic; first order control on basin shape. (long term)
2) sedimento-eustatic; erosion of mountains, etc. (long term)
3) juvenile H2O formation; via vulcanism. (long term)
4) glacial-interglacial. (shorter term)
5) glacial-isostatic; glacial rebound, e.g. Norway (shorter term)
6) hydro-isostatic; loading with water rather than ice (shorter term)
Thermal expansion is a potential source of short-term sea level rise, but not the only one. Melting of ice currently floating in the North Atlantic may have indirect effects on sea level (due to complex ocean-atmosphere interactions), but will not directly cause sea level to change (principle of isostasy).
Now the melting of the Antarctic ice sheet is another matter...
Do a google search on "NADW formation" and you'll find out why Europe's climate is moderate.
The general idea is: warm salty water delivered to the North Atlantic (ie, Gulf Stream) sinks; salinity is directly proportionate to density. As the denser water sinks, it cools, exchanging heat with the atmosphere. An additional factor that influences NADW formation is sea ice formation. When sea ice forms, most of the solutes are left behind, so salinity increases in the North Atlantic with increased sea ice formation.
Any climate changes that decrease salinity will have a negative effect on ocean-atmosphere heat exchange. So, paradoxically, as atmospheric temps rise, less sea ice forms and evaporation increases resulting in less salinity differential and thus decreased NADW formation. Instant European ice age.
This has happened before as the northern hemisphere exited the previous ice age. Meltwater from retreating glaciers was dumped into the North Atlantic, decreasing salinities and shutting down NADW formation. Instant European ice age. This is referred to as the Younger-Dryas event, and it lasted roughly 500 years.