In-flight validation of SPEX airborne spectro-polarimeter onboard NASA's research aircraft ER-2

摘要: High accuracy multi-angle polarimetry is of crucial importance for remote sensing aerosol and cloud properties with accuracies demanded by climate air quality studies. In this contribution, we provide an detailed description the spectro-polarimetric instrument “SPEX airborne” that was developed to operate from NASA’s high altitude research aircraft ER-2. SPEX airborne delivers measurements radiance linear polarization at nine fixed viewports angles equally distributed over total angular range 112°, visual wavelength in 400-760nm. Each viewport acts as a pushbroom spectrometer swath 6°. participated recent ACEPOL campaign October-November 2017 when it flew together Research Scanning Polarimeter (RSP), Airborne Multiangle SpectroPolarimetric Imager (AirMSPI), Hyper-Angular Rainbow (AirHARP). We compare polarimetric radiometric those collected RSP four visible bands. Simultaneous were made while flying widely different scenes, under illumination meteorological conditions. This provided large dynamic values. find Degree Linear Polarization (DoLP) measured both instruments agrees well RMS differences ~0.005 best result 555nm. For excellent agreement obtained difference ~4%. The in-flight comparison results verification airborne’s capability deliver high-quality data.