The Warming Climate Aggravates Atmospheric Nitrogen Pollution in Australia

Australia is a warm country with well-developed agriculture and a highly urbanized population. How these specific features impact the nitrogen cycle, emissions, and consequently affect environmental and human health is not well understood. Here, we find that the ratio of reactive nitrogen (N(r)) losses to air over losses to water in Australia is 1.6 as compared to values less than 1.1 in the USA, the European Union, and China. Australian N(r) emissions to air increased by more than 70% between 1961 and 2013, from 1.2 Tg N yr(−1) to 2.1 Tg N yr(−1). Previous emissions were substantially underestimated mainly due to neglecting the warming climate. The estimated health cost from atmospheric N(r) emissions in Australia is 4.6 billion US dollars per year. Emissions of N(r) to the environment are closely correlated with economic growth, and reduction of N(r) losses to air is a priority for sustainable development in Australia.