Cycling is definitely picking up popularity in the US. As for Europe, I'm not sure. If you ever want to know how much popularity cycling has, go to your local bike shop and ask roughly how many bikes they sell each year. It'll blow you away.
Google the tour de France or lance armstronge
I've noticed a lot of young people riding more, mostly due to the growing popularity of critical mass and fixed gear bikes. For many of them bicycling are just an added feature of the hipster fashion trend
no
In Europe, mostly in France.
if you mean racing? in Europe its Feb - Oct, cycling can be done year round depending on the weather conditions of the locality.
Depends on where you're at. In Europe and North America - certainly. Some parts of Asia probably have more bicycles and scooters than cars though.
for popularity
Europe, late 1970s.
The world's best known cycling race is probably Le Tour de France, which is held in France, which is a country in Europe.
culuture differences
cultural difference within Europe have declined
increasing
Europe's population has been decreasing.
north equatorial