One important implication of this finding concerns the possible energy sources needed to maintain the ocean's large-scale “conveyor-belt” circulation and to mix upper ocean heat into the abyssal depths. It is thought that 2 terawatts are required for this process. The winds supply about 1 terawatt, and there has been speculation that the tides, by pumping energy into vertical water motions, supply the remainder. However, all current general circulation models of the oceans ignore the tides. “It is possible that properly accounting for tidally induced ocean mixing may have important implications for long-term climate modeling”, Egbert said.
In the past, most geophysical theories held that the only significant tidal energy sink was bottom friction in shallow seas. Egbert and Ray find that this sink is indeed dominant, but it is not the whole story. There had always been suggestive evidence that tidal energy is also dissipated in the open ocean to create internal waves,
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