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Wet‐reduced nitrogen (NH4+) is the main component of atmospheric nitrogen (N) deposition. Due to the poor coverage of ground‐based measurements, it is still challenging to characterize the global wet‐reduced NH4+ deposition. Here we utilize NH3 measurements from satellite retrievals (Infrared Atmospheric Sounding Interferometer) to estimate global wet NH4+ deposition at 0.1° grids for nine years (2008–2016). We achieve this by developing a novel approach by calculating the feedback ratio between wet NH4+ concentration in precipitation and atmospheric NH3 columns using a global chemistry transport model (GEOS‐Chem). Satellite‐based wet NH4+ concentration and deposition is relatively highly correlated with the ground‐based measurements (r = 0.88 and bias = 12% for wet deposition). The largest increase in the satellite‐derived wet NH4+ deposition occurs in southern China (>0.5 kg N ha−1 yr−1), followed by northeastern India, North America, and Western Europe. The proposed method is simple, fast, and effective in estimating wet NH4+ deposition using the satellite observations without depending on the ground‐based measurements for constructing the models. It is particularly helpful in estimating wet NH4+ deposition over regions with few monitoring sites. Our unique satellite‐derived wet NH4+ deposition can be applied for evaluating its impacts on ecosystems in the future. Key Points: We present a novel approach for estimating wet‐reduced nitrogen deposition globallyThe proposed satellite‐based model shows better performance than the global atmospheric modelsThe largest increase of wet reduced nitrogen deposition occurs in southern China, followed by northeastern India, North America, and Western Europe [ABSTRACT FROM AUTHOR]

Background and Aims The incidence of inflammatory bowel disease ( IBD) is increasing in China with urbanization and socioeconomic development. There is however a lack of prospective, population-based epidemiology study on IBD in China. The aim of the study is to define the incidence and clinical characteristics of IBD in a developed region of Guangdong Province in China. Methods A prospective, population-based incidence study was conducted from July 2011 to June 2012 in Zhongshan, Guangdong, China. All newly diagnosed IBD cases in Zhongshan were included. Results In total, 48 new cases of IBD (17 Crohn's disease [ CD]; 31 ulcerative colitis [ UC]) were identified over a 1-year period from July 2011. Age-standardized incidence rates for IBD, UC, and CD were 3.14, 2.05, and 1.09 per 100 000 persons, respectively. The median age of UC was 38, and that of CD was 25. Terminal ileum involvement only ( L1), isolated colonic disease ( L2), and ileocolonic disease ( L3) were reported in 24%, 6%, and 71% of patients with CD, respectively. Twenty-four percent of patients had coexisting upper gastrointestinal disease ( L4). Inflammatory ( B1), stricturing ( B2), and penetrating ( B3) behavior were seen in 65%, 24%, and 12% of CD patients, respectively. Fifty-nine percent of CD and 26% of UC patients had extra-intestinal manifestations. Conclusions This is the first prospective, population-based IBD epidemiological study in a developed region of China. The incidence of IBD is similar to that in Japan and Hong Kong but lower than that in South Korea and Western countries. [ABSTRACT FROM AUTHOR]