Where does the energy go when two drops combine?

Question

Recently been studying fluid mechanics and I have a query in context with surface energy.
I am aware that energy is decreased when two drops combine, But not aware of where that energy goes.
Does the temperature of the combined drop increase or is it radiated to the surroundings?
Follow-up question, If it is the first one does that mean after it rains the temperature of the ocean is increased ever so slightly?

Anders Sandberg · Accepted Answer

Initially the energy goes into accelerating the fluid, turning into kinetic energy. If there are interfaces nearby like a superhydrophobic surface this can make the droplet propel itself away from it, but with low efficiency: most energy goes into wobbling that presumably emits some acoustic waves but mostly heats the fluid as the viscosity dampens the oscillations.
For microcopic droplets one can simulate the molecular interactions and it looks like energy proportionally goes into making more hydrogen bonds, but the rest increases the temperature-entropy term.

Where does the energy go when two drops combine?

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