1. The Ultraviolet Visible Hyperspectral Imaging Spectrometer (UVHIS), and high-resolution NO2 mapping from its first airborne observation.
- Author
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Xi, Liang, Si, Fuqi, Jiang, Yu, Zhou, Haijin, Zhan, Kai, Chang, Zhen, Qiu, Xiaohan, and Yang, Dongshang
- Subjects
SPECTROMETERS ,LIGHT absorption ,POLLUTION monitoring ,SOLAR radiation ,OPTICAL spectroscopy ,TRACE gases - Abstract
We present a novel airborne imaging differential optical absorption spectroscopy (DOAS) instrument: Ultraviolet Visible Hyperspectral Imaging Spectrometer (UVHIS), which is developed for trace gas monitoring and pollution mapping. Within a broad spectral range from 200 to 500 nm, operated in three channels, the spectral resolution of UVHIS is better than 0.5 nm. The optical design of each channel comprises a fore-optics with a field of view (FOV) of 40°, an Offner imaging spectrometer, and a charge-coupled device (CCD) array detector of 1032 × 1072 pixels. A first demonstration flight using UVHIS was undertaken on 23 June 2018, above an approximate 600 km
2 area in Feicheng, China, with a spatial resolution of about 25 × 22 m2 . Measurements of nadir backscattered solar radiation of channel 3 are used to retrieve vertical column densities (VCDs) of NO2 with a mean fitting error of 2.6 × 1015 molec cm−2 . The UVHIS instrument clearly detected several emission plumes transporting from south to north, with a peak value of 3 × 1016 molec cm−2 in the dominant one. UVHIS NO2 vertical columns are well correlated with ground-based mobile DOAS observations, with a correlation coefficient of 0.65 for all co-located measurements, and a slight underestimation for polluted observations. This study demonstrates the capability of UVHIS for NO2 local emission and transmission monitoring. [ABSTRACT FROM AUTHOR]- Published
- 2020
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