Let's see if we can unpick some your misunderstandings here.<quoted text>
One of the researchers (Trenberth) states the uptake of heat in the deep oceans will result in a rise in sea level beyond that which occurs from ice melt. This logically means that melt rate estimates are likely in error due to the failure of incorporating thermal expansion resulting from the assumed deep ocean heating.
Ice melt is not estimated from sea level rise- it is measured by satellites.
Sea level also increases as the oceans warm- at any depth. This is already known.
The budget must close- this is true.
Sea level rise must equal expansion due to warming plus ice melt volume.
The thermal expansion in the deep ocean was not incorporated in previous sea level budgets, but those budgets didn't close.
Sea level was more than expansion due to warming plus ice melt volume.
If sea level rise had equalled expansion due to warming plus ice melt volume, and the figure for expansion due to warming had increased, then you would have to assume either the ice melt data were in error, or doubt the deep ocean warming.
But because the budget didn't close, thermal expansion due to deep ocean warming actually explains the observed sea level rise better, and gives more confidence to observations of ice melt.
http://www.skepticalscience.com/deep_ocean_wa...Recent sea level rise has so far been difficult to fully explain: satellites measure global sea level rise since 1993 to be about 3.1 mm/year. The warming and expanding 'upper ocean', or the top 700 metres measured by ships and buoys can explain 1.2 mm/year whilst the water added by melting snow and ice can be estimated from satellite gravity measurements for ice sheets and other methods for smaller glaciers, and is about 0.85 mm/year.
Simple addition of the numbers above (1.2 + 0.85 mm/year = 2.05 mm/year) shows that the result from the upper ocean thermal expansion and addition of water mass is still about 1 mm/year short of the observed 3.1 mm/year sea level rise. However, some previous studies have had these numbers quite close to each other when the uncertainties in the estimates have been considered.
The model simulations give a sea level rise of 1.1 mm/year from the thermal expansion of the deep ocean. When that is added to the 2.05 mm/year calculated above, the result (3.15 mm/year) is remarkably close to the observed rise of 3.1 mm/year (which more accurately is 3.11 mm/year).