Copper is very corrosion resistant - it does produce a very attractive green patina e.g on the roofs of mosques. To eliminate it entirely - constantly paint it - or use Impressed Current Cathodic Protection. I would not bother
when air and water react with copper, it will cause corrosion.add. the common verdigris on copper is usually the carbonate, but close to the ocean, the chloride may be present as well.
The only solution I know of is to make it worse. You add a plug (of some kind) of some metal even more corrodible than your structural metal ... it adsorbs the spare ions to protect your base. Often...