The difference is mostly in the amount of humidity. Continental climates usually have cool summers and cold winters and don't have high humidity. Central European is like continental climate except it has humidity because of the way air drifts work. They are similar but the temperature is usually higher.
I believe the answer is: A just-noticeable difference
In painting, A just-noticeable difference refers to the amount of things that needed to be change for a difference to be noticeable.
The threshold usually depended on the type of audience that being aimed toward, (for common audience, the threshold of differences would be relatively higher compared to expert audience)<span />
Analyzing data collected by others.
I thinks its heat im not sure though
