Left: the effect of the P_n parameter (day-night heat transfer efficiency) on the T − P profile of the atmosphere. The curves are labeled with the values of the P_n parameter and the core entropy, respectively. Notice that the entropy on the day side decreases with increased efficiency of heat redistribution. Entropy on the night side behaves in the opposite way and increases with increasing heat redistribution, or P_n value. Right: the effect of the P_n parameter on the day-night side cooling. The models are calculated for three different values of P_n = 0.1,0.3,0.5. Cooling from the night side decreases with the efficiency of heat redistribution (P_n). Cooling from the day side behaves in the opposite way and increases with increasing P_n. However, the night side is more sensitive to the P_n parameter, so it governs total core heat loss, which decreases with increasing P_n. The difference between night and the day side cooling is largest for the smallest values of P_n.