Acceso usuarios
Ignacio Ayestarán Uriz 
This article explores three recent courses in the global study of sustainability on the Earth. The first section is an overview of the Global Environment Outlook 4: Environment for Development (GEO-4) report, which summarizes the radical and unsustainable transformations developed in the interaction between the biosphere and the noosphere during the last twenty years. The second section presents the Hilbertian program of the Earth System Science proposed by Paul J. Crutzen and Hans Joachim Schellnhuber. They have explained that, due to the human action, we are living in an emerging geological and historical epoch: the Anthropocene. This presupposes a methodological challenge, called by the authors �the second Copernican revolution�. Finally, the third section links this challenge to environmental ethics through the description of the work of Hans Jonas and Tongjin Yang
