Ronald, sea level rise is the issue. It has three components, thermal expansion, icecap melting and the flux between land and sea as aquifers are pumped dry and/or downpours move ocean volume to land as was the case of 2010/11 when sea levels fell 5mm due to deluges in Australia and the Amazon.
Ocean thermal energy conversion addresses the first two of these factors by sapping the energy of storms that move heat to the poles, converting ocean heat to work and moving more to a depth of 1000 meters where the coefficient of expansion of sea water is half that of the surface and by converting liquid volume to gas to create the hydrogen necessary to get the power generated offshore to market.
We can also rectify the aquifer issue by moving water from areas of excess to areas of deprivation.
Unfortunately we are doing none of the above.