Aaron: Ok, I'll bite. Robert Madsen, Dull Knife College has been looking at air movements inside hives with a temperature probe positioned every 1 inch of space in all dimensions. He and I and others are still working to understand the data, but it is pretty clear that convection currents circle the frames. THe hot air moves up, around and over the frames, the hottest spot moving as one might expect with the sun, and changing from day to night. This movement of air around the frames (as a block) seems to be more or less the same, regardless of whether bees are or are not in the box. Its basically hotter air rising and cooler air dropping, moving around the perimeter of the frames. Now, between the frames is a different issue. In this case, the air flow seems to respond to the bees, and how they manage it changes with different situations. They will move hot air toward the part of the hive with the hottest air (in the summer). They often more or less mix the air for maximum uniformity (less than 0.5 degree C difference) throughout the space between any two combs, although the temperature between any two frames may differ. Although we don't fully understand what's going on, we do know that its not a simple chimney, nor are we likely to predict it based on what we THOUGHT we knew. My analogy is that of a car and a heater or air conditioner. We don't run down the road on a very cold or very hot day with the windows open and the vent open. We recirculate the air, rather than exchange the bulk of it with the outside. Same seems to apply to bees in the hive. Yes, they have to generate heat in cold, exhaust heat in hot weather;; but they don't let much warm or cool air, as needed, escape. Jerry :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info --- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::