Bike maintenance in high humidity conditions????

[Hendrik Petoors]

I have always lived in fairly dry conditions. Even in Mozambique that was 100km form the coast. We now live 1 km from the sea. I see that the flat areas on the "spokes" or radians of the disk rotors there is light rust forming. On the chainblades I can spray light oil, but light oil WILL be disastrous on the disk rotors. Centrifucal force will spin the oil onto the brakings surfaces of the rotors. What do I do????? Do I just live with it and regularly clean with a 3M scouring pad? We live in a hotelroom with our Tandem. It is airconditioned and with power failures the whole room "dews" wet. Not very dry conditions!!!!!