I remember the time when it was advised to bag the roof turbines during winter. But, now that is strictly taboo.
Ventilation is necessary regardless of the time of year. You need to stop at any cost the build up of condensation or humidity regardless of the time of year.
I would close off some, but allow enough open for a gentle vent of the area. I would not have the northern vents open, but maybe the east and west ones. Your aim is to not cause an ice box, but not to cause it to be warmer than outside to build up dampness.