Simulation and analysis studies of SWIFT measurements

The Stratospheric Wind Interferometer For Transport studies (SWIFT) is a limb viewing satellite instrument designed to measure winds in the stratosphere using Doppler shifts in a thermal emission line from ozone at about 8.8 micron. The expected wind accuracy is 5 ms-1 or better. The instrument simultaneously measures the ozone concentration so that transport of ozone will also be studied.; The objective of this instrument is to extend space-based upper atmospheric wind measurement techniques, previously developed for WINDII, the WIND Imaging Interferometer on the UARS satellite, down into the stratosphere in order to investigate the dynamics of this region. Phase-stepping interferometry, field widening and imaging are the three basic optical techniques that SWIFT employs. So the applied method can be called Doppler Michelson Imaging Interferometry. The instrument has been selected by Japan for the GOSAT mission, formerly GCOM-A1, to be launched in 2008.; This research involved instrument simulations, measurement simulation and data processing, which are being used to assess instrument performance and test the SWIFT data reduction algorithms. In this research the author used modeled IR atmospheric radiances (created by a radiative transfer model) and instrument design characteristics to simulate the expected SWIFT observations. The simulations were repeated for various design options in order to quantify the expected SWIFT wind errors.; The measurement simulation and data processing along with inversion results suggest that the SWIFT instrument will meet the measurement requirements of wind error of 3--5 ms-1 for the altitude range of 20--45 km as well as the required ozone concentration accuracy.