"World Environment Day, commemorated each year on 5 June, is one of the principal vehicles through which the United Nations stimulates worldwide awareness of the environment and enhances political attention and action."
From "About World Environment Day".
<sarcasm>I am sure that statements containing phrases like "principal vehicles" will really appeal to the masses.</sarcasm>
Happy World Environment Day, everyone. Celebrations are in San Francisco, California, so I don’t think I will be able to make it somehow.
For other significant things about today, see the BBC's resource.