This updated version further develops the Planetary Boundaries concept, which was first published in 2009.  In their original outline of the concept the authors identified nine key global processes and systems that regulate the stability and resilience of the Earth System – the interactions of land, ocean, atmosphere and life that together provide conditions upon which our societies depend.  They argued that if these natural processes are disrupted beyond a certain ‘boundary’ point, the consequences could be irreversible and lead to abrupt environmental change, making life on earth very hard for humans.

Nitrogen is a necessary element for crop and livestock growth, and protein intake is essential for a balanced human diet. This study examines efforts to improve nitrogen use efficiency (NUE) in agriculture, and reduce unintended losses of nitrogen (N) to the environment. The paper particularly looks at how it is possible to offset reactive nitrogen (Nr) and achieve so called nitrogen-neutrality.

A new study from researchers at The Earth Institute of Colombia University and the Woods Hole Research Center says emissions of nitrous oxide could double by the middle of the century if left unchecked. Nitrous oxide is the third biggest contributor to human-induced climate warming after carbon dioxide and methane.

Ten years after the first Year Book in this series appeared, a special e-book anniversary edition – UNEP Year Book 2014 – presents a fresh look at ten issues highlighted over the past decade.

This report quantifies how much our food choices affect pollutant nitrogen emissions, climate change and land use across Europe.