SCIAMACHY: Mission Objectives and Measurement Modes

Abstract

SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) is a spectrometer designed to measure sunlight transmitted, reflected, and scattered by the earth's atmosphere or surface in the ultraviolet, visible, and near-infrared wavelength region (240-2380 nm) at moderate spectral resolution (0.2-1.5 nm, /⌬ ഠ 1000-10 000). SCIAMACHY will measure the earthshine radiance in limb and nadir viewing geometries and solar or lunar light transmitted through the atmosphere observed in occultation. The extraterrestrial solar irradiance and lunar radiance will be determined from observations of the sun and the moon above the atmosphere. The absorption, reflection, and scattering behavior of the atmosphere and the earth's surface is determined from comparison of earthshine radiance and solar irradiance. Inversion of the ratio of earthshine radiance and solar irradiance yields information about the amounts and distribution of important atmospheric constituents and the spectral reflectance (or albedo) of the earth's surface. SCIAMACHY was conceived to improve our knowledge and understanding of a variety of issues of importance for the chemistry and physics of the earth's atmosphere (troposphere, stratosphere, and mesosphere) and potential changes resulting from either increasing anthropogenic activity or the variability of natural phenomena. Topics of relevance for SCIAMACHY are R tropospheric pollution arising from industrial activity and biomass burning, R troposphere-stratosphere exchange processes, R stratospheric ozone chemistry focusing on the understanding of the ozone depletion in polar regions as well as in midlatitudes, and R solar variability and special events such as volcanic eruptions, and related regional and global phenomena. Inversion of the SCIAMACHY measurements enables the amounts and distribution of the atmospheric constituents O 3 , O 2 , O 2 (1 ⌬), O 4 , BrO, OClO, ClO, SO 2 , H 2 CO, NO, NO 2 , NO 3 , CO, CO 2 , CH 4 , H 2 O, N 2 O, and aerosol, as well as knowledge about the parameters pressure p, temperature T, radiation field, cloud cover, cloudtop height, and surface spectral reflectance to be determined. A special feature of SCIAMACHY is the combined limb-nadir measurement mode. The inversion of the combination of limb and nadir measurements will enable tropospheric column amounts of O 3 , NO 2 , BrO, CO, CH 4 , H 2 O, N 2 O, SO 2 , and H 2 CO to be determined.

Global validation of SCIAMACHY limb ozone data (versions 2.9 and 3.0, IUP Bremen) using ozonesonde measurements

“…The SCIAMACHY instrument operated from August 2002 to April 2012 on board the European satellite Envisat (Burrows et al, 1995;Bovensmann et al, 1999). Envisat operated in a sun-synchronous, near-polar orbit with a local equatorial overpass time at around 10:00. at the descending node.…”

“…For satellite instruments, different observation techniques including solar/stellar occultation measurements (e.g., SAGE -Stratospheric Aerosol and Gas Experiment (McCormick et al, 1989); HALOE -Halogen Occultation Experiment (Russell et al, 1994); ACE -Atmospheric Chemistry Experiment (McElroy et al, 2007); GOMOSGlobal Ozone Monitoring by Occultation of Stars (Bertaux et al, 2010)), limb scatter/emission measurements (e.g., MLS -Microwave Limb Sounder (Waters et al, 2006); MIPAS -Michelson Interferometer for Passive Atmospheric Sounding (Fischer et al, 2008); OSIRIS -Optical Spectrograph and InfraRed Imager System (Llewellyn et al, 2004)) and nadir measurements (e.g., GOME/GOME2 -Global Ozone Monitoring Experiment Callies et al, 2000); OMI -Ozone Monitoring Instrument (Levelt et al, 2006); IASI -Infrared Atmospheric Sounding Interferometer (Clerbaux et al, 2009)) are used (see, e.g., Sofieva et al, 2013;Hassler et al, 2014, and references therein). The passive imaging spectrometer used in this study, SCIA-MACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY), provided vertical distributions of atmospheric trace gases by employing the limb-scattering measurement technique (Burrows et al, 1995;Bovensmann et al, 1999).…”

A method for colocating satellite <i>X</i><sub>CO<sub>2</sub></sub> data to ground-based data and its application to ACOS-GOSAT and TCCON

“…One important measure of CO 2 is total column carbon dioxide (X CO 2 ), which is available from ground-based Total Carbon Column Observing Network (TCCON; Wunch et al, 2011a) and from space-based satellite instruments such as the Greenhouse gases Observing Satellite (GOSAT; Yokota et al, 2004;Hamazaki et al, 2005) and the SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY; Bovensmann et al, 1999).…”

Tropical tropospheric ozone column retrieval for GOME-2

“…Tropical tropospheric ozone has been inferred from a number of instruments, including GOME (Burrows et al, 1999), SCIAMACHY (Bovensmann et al, 1999), IASI (Clerbaux et al, 2009), OMI (Levelt et al, 2006) and MLS . Several techniques have been used to retrieve tropospheric ozone columns, such as the tropospheric ozone residual (TOR) method using OMI total ozone and MLS stratospheric ozone column measurements (Ziemke et al, 2006;Schroeberl et al, 2007), the direct retrieval of tropospheric ozone (e.g.…”