I found an interesting campaign about climate change which is called “climate witness” held by WWF. This project is not like a big march or one-shot campaign but an internet based and more long-term activity. On “Climate witness” web page, there are photos, movies and words of witnesses of global warming from all over the world. They speak about what is happening because of the global warming for people who cannot get how global warming is a serious problem.
It’s going to be easy and effective campaign if it becomes well known but since it is not a showy one, it is not so known by everyone which I guess there are some problems to solve to make it significant.