Ground-based measurements with the Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) engineering demonstration unit – experiment description and first results

The Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) Engineering Demonstration Unit (EDU) is an imaging infrared spectrometer designed for atmospheric soundings. It measures the infrared spectrum in two spectral bands (14.6 to 8.8 µm, 6.0 to 4.4 µm) using two 128×128 detector arrays with an unapodized spectral resolution of 0.57 cm-1 (i.e., with a maximum optical path difference of ~0.88 cm) and a full spectral resolution scan duration of ~11 seconds. From a geosynchronous orbit, the instrument will have the capability of taking successive measurements of different geographical areas to scan any desired region of the globe, from which atmospheric temperature and moisture soundings, cloud and surface parameters, wind profiles, as well as other derived products can be retrieved. The GIFTS EDU provides a flexible and accurate testbed for the new challenges of the emerging hyperspectral era. The EDU ground-based measurement experiment, held in Logan, Utah during September 2006, demonstrated extensive capabilities and the potential for geosynchronous satellite and other platform Earth observing environmental measurements. This paper addresses the ground-based experiment objectives and provides “first-look” results illustrating the overall performance of the sensor system with a focus on the GIFTS EDU imaging capability and proof of the GIFTS measurement concept.