It corresponds to a toponymic type frequently found in Christian Gaule, that gave different variants depending on the region: Joué (west of France), Jouy (center and north), Jouey (east), Gouy (Normandy/Picardy), Gaugeac, Jaujac (south).
Knowler is an uncommon English surname, a toponymic derived from knoll (Old English cnoll), with the suffix -er common in Kent and Sussex.
"Océano" (with accent) is the Spanish word for "ocean", but the toponymic name is written without it.
Toponymic Guidelines (full title: Toponymic guidelines for map and other editors, for international use) are up-to-date documents promoted by the United Nations Group of Experts on Geographical Names (UNGEGN).