The Mechano-Molecular Ocean Frontier

Dissipation of the 1[Formula: see text]TW of kinetic energy as heat in the ocean by “friction” is governed by the requirement to overcome the activation energy of viscous flow. This is accomplished by physically forcing the breaking of a hydrogen bond, typically from the Walrafen tetrahedral pentamer form, creating a new single H 2 O molecule as the active species. For viscous flow to occur, one molecule must slide by another to occupy a new location, thus requiring a space for the transposed molecule to move into. The formation of a new single H 2 O molecule with an associated new hole in the fluid is the minimum energy pathway to achieve this. The activation energy of viscous flow of seawater for 35[Formula: see text]per mille salinity is 17.89[Formula: see text]kJ/mol, yet the hydrogen bond strength in seawater is 9.447[Formula: see text]kJ/mol. The large energy penalty of 8.443[Formula: see text]kJ/mol required to allow flow to proceed is testimony to the remarkable stability of the hydrogen-bonded molecule. This excess energy is released as highly localized heat and permits additional molecular translations to follow. Seawater does not have an unusually high viscosity, but a high activation energy of viscous flow. Once that energy barrier is surmounted, water can flow with remarkable ease.