World Environment Day:

World Environment Day (WED) was established by the United Nations General Assembly in 1972. WED is hosted every year by a different city and commemorated with an international exposition through the week of June 5. The United Nations Environment Programme (UNEP), also created in 1972, uses WED to stimulate awareness of the environment and enhance political attention and public action.
The theme for WED 2009 is 'Your Planet Needs You - UNite to Combat Climate Change'. It reflects the urgency for nations to agree on a new deal at the crucial climate convention meeting in Copenhagen some 180 days later in the year, and the links with overcoming poverty and improved management of forests.
WED 2009’s host is Mexico which reflects the growing role of the Latin American country in the fight against climate change, including its growing participation in the carbon markets.
Mexico is also a leading partner in UNEP's Billion Tree Campaign. The country, with the support of its President and people, has spearheaded the pledging and planting of some 25 per cent of the trees under the campaign. Accounting for around 1.5 per cent of global greenhouse gas emissions, the country is demonstrating its commitment to climate change on several fronts.