Do you have any reference for this ? The article says nothing about that.
It says that sound travels further in a channel of cold air between warmer air and ground (it could be water even better).
I think it's the opposite: in lower temperature the air density is bigger and it's mass so energy to move the same mass shall exhaust (heat) at shorter distance..
I think it's the opposite: in lower temperature the air density is bigger and it's mass so energy to move the same mass shall exhaust (heat) at shorter distance..