Data Analysis

The raw SCISAT data is downlinked to ground stations in Saskatoon, St. Hubert, Alaska and Kiruna. The data volume, which at times can exceed 3 Gb per day, is transferred to the Mission Operations Centre operated by Canadian Space Agency in St. Hubert (near Montreal) then sent to the Science Operations Centre at the University of Waterloo. At Waterloo the data is archived and processed to obtain data products for distribution to the science team members.

Atmospheric temperature profiles are determined as a function of pressure by starting with a priori data from an upper atmospheric model combined with meteorological data from the Canadian Meteorological Centre for improved accuracy in the troposphere and lower stratosphere. An empirically determined CO2 volume mixing ratio is used for the ACE-FTS and O2 A-, B- and Gamma-bands for MAESTRO. Both ACE-FTS and MAESTRO solar occultation measurements are converted to height profiles of atmospheric species. The ACE-FTS algorithm for retrieval of atmospheric profiles has some similarities to the ATMOS algorithms but applies a more sophisticated global fit approach, developed by and described in detail by Boone et al. [2005]. The MAESTRO algorithms draw on previous work by McElroy and co-workers with a variety of UV/visible spectrographs that have been deployed.