I think you are correct adagna.
The frames perpendicular to the entrance mean that there is increased airflow, which cools the hive when the air outside is cooler than the air inside the hive.
Turn the frames 90° or move the entrance, so that the frames run parallel to the opening and you reduce airflow by blocking the open path ways for ventilation.
I hadn’t much thought about this before, but in areas where the summers are very hot and the winters are very cold it might be worth having sets of bottom boards, to exchange seasonally, to aid the hive in maintaining an optimal temp.
Or has anyone come up with a bottom board design that easily converts between the two? That would be nifty.
We are in a mild marine climate here in San Francisco, with little variation between the median highs and lows year round, but I suspect many areas would benefit from such an arrangement.