The worldwide annual Earth Day always fall on April 22 and has been celebrated since its inception in 1970.
The central purpose of the day is to call on action from organizations to invest into green initiatives and to mobilize millions of people to create a sustainable, healthy environment by participating in community initiatives or larger global organizations.
Every year millions of people celebrate earth day by participating in different events, singing petitions, holding demonstrations, and raising awareness.
A global organization Earth Day Network, for example, launched a campaign in 201o to register one billion “Acts of Green” prior to the United Nations Conference on Sustainable Development in June 2012. Earth Day Network’s A Billion Acts of Green, largest environmental service campaign in the world, is an accumulation of individual acts and larger organization initiatives that reduce carbon emission and support sustainability.
The organization reached that goal, and with over one billion and 19 million acts on April 21, 2014, the organization encouraged those interested to help the organization reach over 2 billion registered actions. You can register your act here.
You can check for a sample list of events happening around the world during Earth Day on April 22, 2014 here.