Incredible finding!
The cold surface sea water that keeps the Galapagos dry is part of a basin-scale structure called the equatorial cold tongue, and is known to originate from beneath the surface.
...the equatorial cold tongue [figure above] is a tale of remarkable interactions across eight orders of magnitude, from turbulence (10-1 m) to the size of the vast Pacific Ocean (107 m).
Climate science: Unequal equinoxes
by Shang-Ping Xie
This is amazing once you consider the size scales involved. The extent of the equatorial cold tongue reaches from about the Galapagos Islands west to about Jarvis Island, an arc of about 69°. If you factor in the average depth of the Pacific ocean, about 2000 meters, it looks about like this scale diagram:
