Redefining environmental sustainability

摘要

Human activities are rapidly changing both positively and negatively the Earth system and its components at local, regional and global scales. Greenhouse gas emissions continue to increase in most regions [1]. The atmospheric carbon dioxide concentration has just passed the elicit boundary of 400 ppm. Oceans are acidifying and arctic ice was at its lowest observed extent ever in September 2012 [2]. Land use is intensifying in many places and biodiversity continues to decline [3]. The human population surpasses seven billion and, although at a slower pace, is still increasing. The global economy valued at market price has grown tenfold over the past decades and will continue to expand, not only in the developed world but also in the emerging economies in Asia, Africa and Latin America. But the benefits of this development are not shared by all. Distributive justice is getting