Atmospheric ammonia (NH3) is a trace gas that causes environmental problems and is harmful to human health.
Chinese scientists have developed a fully physical retrieval algorithm to derive the concentration of the atmospheric ammonia from the Hyperspectral Infrared Atmospheric Sounder (HIRAS) on board China's FengYun (FY)-3D satellite, presenting the first atmospheric NH3 column global map observed by the HIRAS instrument.
The study was conducted by ZHOU Minqiang, an associate researcher from the Institute of Atmospheric Physics of the Chinese Academy of Sciences, in collaboration with ZHANG Xingying, a senior researcher of the China Meteorological Administration.
Dr. ZHOU Mingqiang, lead author of the study, emphasizes the significance of this landmark achievement, saying that monitoring global atmospheric ammonia levels is critical to understanding its environmental impact and influence on climate change. "The HIRAS instrument's ability to detect NH3 hotspots worldwide represents a significant leap forward in our ability to track and understand its spatiotemporal distribution," he says.
The HIRAS NH3 columns were compared with measurements from the Infrared Atmospheric Sounding Interferometer, a hyperspectral infrared sounder residing on the European Space Agency's MetOp series of polar-orbiting satellites, showing good consistency between the two instruments, thus verifying the reliability of the ammonia observation from the FY-3D satellite.
"This aligns with our efforts to utilize multiple satellite instruments for a holistic understanding of atmospheric ammonia dynamics," said Prof. ZHANG Xingying, corresponding author of the study.
Challenges still remain ahead. "Although our study marks a significant leap forward, we are still making efforts to refine the HIRAS NH3 retrievals. Continued research aims to reduce the uncertainty of satellite-based NH3 monitoring for a comprehensive understanding of its global impact," said ZHANG.
This groundbreaking work marks a significant step forward in Chinese satellite-based atmospheric monitoring and provides important insights into the global distribution of NH3. The results hold promise to advance our understanding of atmospheric composition and its implications for environmental and climate studies.
Satellite remote sensing is a unique technique for globally monitoring the Earth's environment. Red and yellow shading indicates regions with a high NH3 concentration around the world, e.g., India, West Africa, and East China. (Image by AAS)
