Thank you for these quotes from Farrar!  Let's take a look at them.

>The cluster does not radiate heat to the unoccupied part of the hive, as a
> stove radiates heat to a room.
>
This was an obvious misunderstanding.  In fact just yesterday I was
demonstrating the difference infrared radiation is from a cool wall vs. a
human body.  Easy to demonstrate by facing a cool wall, and holding your
hand between you and the wall, with your palm facing the wall.  Your palm
will quickly feel cool.  Turn your palm to face your body, and despite zero
change in the air temperature, your palm will immediately feel warmer.
The same thing will occur through any space between the outer cluster, and
the closest cooler surface, whether it is a comb or the wall of the hive.
If the temperature outside the hive is below 9C (48F), the cluster will
radiate heat outward.

>
> >The entrance of the hive when reduced bears a similar relation to this
> unoccupied space as an open door does to a full sized room.
>
For a 20-ft room with a 3-ft door the opening area vs room volume ratio is
0.63%.
For a single Langstroth deep with a 3/8" x 3" opening, the ratio is 0.04%.
And for a double-deep hive, only 0.02%.
Plus the hive opening is much closer to the floor.
So, no, there is not a similar relation!

>
> >Temperatures indicate that extra heavy insulation does not prevent low
> temperatures from reaching the cluster ...

This is the claim that Derek is addressing.  His data and calculations
suggest otherwise.


> heavy insulation is equally effective in retaining low temperatures within
> the hive when the outside temperature begins to rise.
>
This is a very valid concern, since any beekeeper can observe how the
cluster moves to the warm side of the hive, and initiates brood rearing
when the ambient temperature begins to reach around 10C (50F).

So I applaud those such as Derek, with a background in thermodynamics and
fluid mechanics to evaluate and challenge our "common knowledge."  There is
likely a reason that no paper wasps attempt to winter in waterproofed paper
nests.

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