If you want tostudy carp keep a couple of goldfish in a pond.
if the fish are not feeding well inthe pond they will not be feeding wellin a lake
carpdo not feed well when cold they may mouth baits and get hooked.
If you want to kill fish in cold weather use indigestable feed containing fat and starch, nuts,dog food,meat,corn.OK as ahookbait
Bulk pellets designed for fishfarming are mutch safer as a feed
A good smell may stimulate interest, water soluble solutions will work better in cold.
In the cold fish will be where most comfortable same as us,and will move to a different position in different conditions, perfect example would be in a deep sheltered bay near the edge in the sun either side of the wind, quicker for you to find fish than them to find you.
I would use one rod and move rig often to find the spot, using a small bag of dry casters or pellets dampened with attractent eg ribena and coated with powder eg fivespice, with half a lobworm and a peice of yellow popup on a hair.
I am not a dedicated carp fisherman and am just as happy catching daceor shark if anyone wants to take me somewhere interesting im'e there, got time and money, based in north Surrey, fish anywhere.