Abstract:
The spatial distribution characteristics of atmospheric ammonia (NH
3) in East Asia from June to September 2008–2011 were investigated using data from the Michelson interferometer for passive atmospheric sounding on the ENVISAT satellite, the AIRS detector on the Aqua satellite, and the global atmospheric chemistry–climate model EMAC. The results show that the highest concentration of NH
3 near the surface appears in northern India, and deep convection exists in the Bay of Bengal near northern India in summer. This deep convection can transport short-lived NH
3 to the upper troposphere and lower stratosphere (UTLS) because of the high altitude of the Qinghai-Tibet Plateau. Therefore, an upward transport column of NH
3 over the Qinghai-Tibet Plateau exits and is the main channel for the upward transportation of NH
3. During the Asian summer monsoon, the location of the Asian summer monsoon anticyclone dominates the spatial distribution of NH
3 in the UTLS area. The high-concentration center of NH
3 continues to exist during the anticyclone, and its position corresponds well with the position of the anticyclone center. During the anticyclone, one or two NH
3 high-concentration centers exist in the anticyclone center, implying that a change in the circulation pattern of the anticyclone has important effects on the NH
3 distribution.