The first trees emerged about 400 million years ago. Humanity needs only about 18,000 years more to destroy them completely. This estimate is overly simplistic and assumes a “no change” scenario from current trends in deforestation—an annual average loss of -0.13 percent—but it forces us to examine the data from a what if perspective, keeping in mind that forests are one of the most important natural filters and producers of oxygen.

One person needs 6 to 9 trees to maintain life, assuming that a single tree produces 100 kg of oxygen per year on average and humans require 740 kg of oxygen per year on average.

Humans of course are not alone in requiring oxygen to sustain life. The decline in total forested area contributes to the extinction of animal and bird species. Since 1998, the number of threatened species of plants and animals have increased by more than 120 percent from 10,533 to 23,250 species, according to the International Union for Conservation of Nature and Natural Resources.

The 1992 Rio Earth Summit was viewed as the turning point for global environmental policy, seeking to overturn disruptive ecological and environmental trends compounded by the industrial revolution and to spur development of national-level environmental policies to address emerging issues. The persistence of deforestation for land clearing and the continued popularity of wood in building and manufacturing despite the critical volume of forest coverage required is (disturbingly) evident in the data.