Important tire pressure

As I mentioned in the last blog, my son ran about all over Hokkaido few days ago spending a week by means of his car, Honda Step Wagon wearing all wheel drive construction.  According to his opinion, in spite of tire pressure checking as to be 240 kpa for front at Osaka before departure, he could not drive it with certain stability. Luck of tire pressure there was the reason, then he adjusted them following the caution decal adequately. On the other hand, he felt some inconvenience on tire pressure after coming back to Osaka, too high pressure here.
The comparison of atmospheric condition, about 10 degree in Osaka, minus 20 degree in Hokkaido shows a fundamental physical difference, 30 degree is the factor for the vehicle's safety not to be lost.
As for my car, I make it a rule to check and to adjust tire pressure as a periodical maintenance every month. On my perception, 10 degree Celsius temperature causes 13 kpa fluctuation.
Deeper consideration leads us to the conclusion that an only surface to contact with the ground is nothing but a tire touching plane just the same as post card, however high performance car it may be.