Evaluation of photochemical grid models (UAM-IV, UAM-V, and the ROM/UAM-IV couple) using data from the Lake Michigan ozone study (LMOS)

Six automatic ammonia analyzers were studied both in the field and in an environmental test chamber to determine their suitability for the Netherlands National Air Quality Monitoring Network (NAQMN). The instruments studied were a continuous-flow denuder, a WO3-coated thermodenuder, a V2O5-coated thermodenuder, a commercial Differential Optical Absorption Spectroscopy (DOAS) system, a photoacoustic monitor, and a chemiluminescence NOx monitor with NH3 converter. In the environmental test chamber functional parameters such as range, precision and detection limit were determined, while the field study was mainly addressed to operational and technical performance of the instruments.