Nighttime NOx from SCIAMACHY lunar occultation measurements
Leonard K. Amekudzi(1), Astrid Bracher(1), Hienrich Bovensmann(1) and John P. Burrows(1)
(1) University of Bremen, Otto-Hanns Allee 1, 28334 Bremen, Germany
Vertical profiles of stratospheric NO2 and NO3 have been retrieved
from moderately resolution atmospheric lunar transmission spectra measured by SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) on board the ENVISAT (Environmental Satellite). The measurements were taken over the high Southern latitude (60°S - 90°S).The global spectra fitting method by differential optical depth approach were used to fit NO2 and NO3 using the spectral window of 430-460 nm and 615-680 nm respectively. To assess the accuracy of the retrieved NO2 profiles the SCIAMACHY nighttime NO2
profiles were compared with daytime NO2 profiles measured by Halogen
Occultation Experiment (HALOE), Polar Ozone and Aerosol Measurement
(POAM-III), and the Stratospheric Aerosol and Gas Experiment (SAGE-III) using photo chemical correction model. The validation results show that the quality of SCIAMACHY nighttime NO2 is high within 15-30% in the altitude range of 20-40 km.
The accuracy and internal consistency of the retrieved NO3 profiles were verified by comparing the retrieved profiles with model calculated NO3 profiles. The model calculated results are in agreement with the retrieval outputs.
Keywords: ESA European
Space Agency - Agence spatiale europeenne,
observation de la terre, earth observation,
satellite remote sensing,
teledetection, geophysique, altimetrie, radar,
chimique atmospherique, geophysics, altimetry, radar,