et al. 2011, Xu et al. 2015, 2018a, b) which measures wet/bulk N deposition and
concentrations of five major N r species (gaseous NH 3 , NO 2 and HNO 3 and particulate NH 4
+ and NO 3
À ) (Fig. 3.1). In addition, the Chinese Ecosystem Research
Network (CERN), founded in 1988, maintains the wet N deposition measurements
(Zhu et al. 2015) (Fig. 3.1).
3.3.2 Satellite Monitoring Instruments
Atmospheric NO 2 and NH 3 can be measured by remote sensing technology. NH 3
can be detected by the Atmospheric Infrared Sounder (AIRS), Cross-track Infrared
Sounder (CrIS), Tropospheric Emission Spectrometer (TES) and Infrared Atmospheric Sounding Interferometer (IASI) (Zhu et al. 2013; Shephard and Cady-Pereira
2015; Warner et al. 2016), while NO 2 can be detected from the Ozone Monitoring
Instrument (OMI), Global Ozone Monitoring Experiment (GOME), GOME-2 and
Fig. 3.1 Distribution of monitoring sites in the Nationwide Nitrogen Deposition Monitoring
Network (NNDMN, sites in red colour) and the Chinese Ecosystem Research Network (CERN,
sites in blue colour)
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