Surveillance, recon and range of weapons has drastically changed. Satellites have the capability to identify a surface fleet and long range weapons are now able to be fired from long distances, find and hit their targets.
I think a couple submarines can effectively negate a carrier task force by just forcing the task force to keep their distance by the threat of a missile launch coming from a patch of seemingly empty see. Any surface ship hunting them is at risk of suddenly becoming the hunted themselves by the submarine or by any land based defense system that are in range.
They are just AC units in reverse. The biggest effect humidity is going to have is on how much condensation is going to form on the exterior radiator. That’ll form frost that’ll have to be melted in a defrosting cycle. That’ll decrease performance and efficacy. Low humidity should keep that to a minimum.