I understand it was an attempt at humor, but there is no line that divides Northern and Southern Europe. Western Europe is in between both (like Central America is in between North and South America).
Also, ‘the Mediterranean’ is not the same as Southern Europe. For instance, France, Monaco, and Corsica are not part of Southern Europe, even though they are in the Mediterranean. Portugal is in Southern Europe, but it isn’t in the Mediterranean.
This post-Cold War classification is somewhat oversimplified.. The category of Central Europe (or Middle Europe) is more helpful in understanding the divisions. Vide "The stolen West..." by Kundera, for example
http://en.wikipedia.org/wiki/File:Europe_subregion_map_UN_ge...
Also, ‘the Mediterranean’ is not the same as Southern Europe. For instance, France, Monaco, and Corsica are not part of Southern Europe, even though they are in the Mediterranean. Portugal is in Southern Europe, but it isn’t in the Mediterranean.