Research on calibration radiation fields of hyperspectral greenhouse gases monitoring instrument

Abstract

The GF-5 satellite equipped with Greenhouse Gases Monitoring Instrument was launched successfully on May 9,2018. The load adopts the principle of spatial heterodyne spectroscopy for super-resolution spectroscopy. Before launch, the research team has carried out a lot laboratory calibration work and designed an on-board calibration system to ensure the accuracy and stability of data quantification to the greatest extent. The on-orbit calibration is closer to the spectral characteristics of the load on-orbit observation data, which can be complementary to the laboratory and on-board calibration. The premise of site calibration is to select a suitable and effective radiation calibration field. For the spatial heterodyne interference greenhouse gas load with large field of view, non-imaging, and hyperspectral characteristics, this paper studies the surface characteristics, radiation characteristics and atmospheric environmental characteristics of the site, put forward the screening conditions and evaluation methods of site calibration radiation field that meet the characteristics of GMI. Based on the established screening criteria, the selection of GMI calibration sites has been carried out on a global scale and multiple effective calibration sites have been obtained. Observation data that meets the calibration requirements have been collected within the scope of the site, which is the basis for the next step of site determination. The acquisition of standard coefficients has laid the foundation.