However, effectively extracting quantitative atmospheric information from the observations is challenging due to the large number of hyperspectral sensor channels, interchannel correlations, associated observational errors, and susceptibility of the results to influence by trace gases. This study
explores the potential of FY-3E/HIRAS-II to atmospheric loadings of SO₂ from volcanic eruptions. A methodology for selecting SO₂ sensitive channels from the large number of hyperspectral channels recorded by FY-3E/HIRAS-II is presented. The methodology allows for the selection of SO₂-sensitive channels that contain similar information on variations in atmospheric temperature and water vapor for minimizing the influence of atmospheric water vapor and temperature to SO₂. A sensitivity study shows that the difference in brightness temperature between the experimentally selected SO₂ sensitive channels and the background channels efficiency removes interference signals from surface temperature, atmospheric temperature, and water vapor during SO2 detection and inversion. A positive difference between near-surface atmospheric temperature and surface temperature enables the infrared band to capture more SO₂ information in the lower and middle layers. The efficiency of FY-3E/HIRAS-II SO₂ sensitive channels in quantitatively monitor volcanic SO₂ is demonstrated using data from the 29 April 2024 eruption of Mount Ruang in Indonesia. Using FY-3E/HIRAS-II measurements, the spatial distribution and quantitative information of volcanic SO₂ are easily observed. The channel selection can significantly enhance the computation efficiency while maintain the accuracy of SO2 detection and retrieval, despite the large volume of data.