资源环境科技发展态势分析平台

Since the industrial revolution, human activities have dramatically changed the nitrogen (N) cycle in natural systems. Anthropogenic emissions of reactive nitrogen (N_r) can return to the earth's surface through atmospheric N_r deposition. Increased N_r deposition may improve ecosystem productivity. However, excessive N_r deposition can cause a series of negative effects on ecosystem health, biodiversity, soil, and water. Thus, accurate estimations of N_r deposition are necessary for evaluating its environmental impacts. The United States, Canada and Europe have successively launched a number of satellites with sensors that allow retrieval of atmospheric NO₂ and NH₃ column density and therefore estimation of surface N_r concentration and deposition at an unprecedented spatiotemporal scale. Atmosphere NH₃ column can be retrieved from atmospheric infra-red emission, while atmospheric NO₂ column can be retrieved from reflected solar radiation. In recent years, scientists attempted to estimate surface N_r concentration and deposition using satellite retrieval of atmospheric NO₂ and NH₃ columns. In this study, we give a thorough review of recent advances of estimating surface N_r concentration and deposition using the satellite retrievals of NO₂ and NH₃, present a framework of using satellite data to estimate surface N_r concentration and deposition based on recent works, and summarize the existing challenges for estimating surface N_r concentration and deposition using the satellite-based methods. We believe that exploiting satellite data to estimate N_r deposition has a broad and promising prospect.