Copyright 2000 Society of Photo-Optical Instrumentation Engineers. This paper was published in the proceedings of the SPIE, Second SEPI International Asia-Pacific Symposium on Remote Sensing of the Atmosphere, Environment, and Space, 9-12 October 2000; Sendai, Japan, and is made available as an electronic preprint with permission of SPIE. One print may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited. Hyperspectral remote sensing of atmospheric profiles from satellites and aircraft W. L. Smith a , D.K. Zhou a , F.W. Harrison a , H.E. Revercomb b , A.M. Larar a , A.H. Huang b , B.Huang b , a NASA Langley Research Center, 100 NASA Road, Hampton, VA 23681-2199 b University of Wisconsin, 1225 W. Dayton Street, Madison, WI 53706 Abstract A future hyperspectral resolution remote imaging and sounding system, called the GIFTS, is described. An airborne system, which produces the type of hyperspectral resolution sounding data to be achieved with the GIFTS, has been flown on high altitude aircraft. Results from simulations and from the airborne measurements are presented to demonstrate the revolutionary remote sounding capabilities to be realized with future satellite hyperspectral remote imaging/sounding systems. 1. Introduction A new era is about to begin in hyperspectral remote sensing, namely the implementation of hyperspectral remote sounding systems. The Geostationary Imaging Fourier Transform Spectrometer (GIFTS), selected for flight demonstration as NASA’s New Millennium Program Earth Observing-3 (EO-3) Mission, combines new and emerging sensor and data processing technologies to acquire geophysical measurements that lead to revolutionary improvements in meteorological observations and forecasting. The GIFTS uses a large area format focal plane detector array (128 x 128) in a Fourier Transform Spectrometer (FTS) 1,2 mounted on a geostationary satellite to enable the simultaneous gathering of high spectral resolution (as great as 0.3 cm –1 ) and high spatial resolution (4-km x 4-km pixel) Earth infrared radiance spectra over a large area (512-km x 512-km) of the Earth within a 10 second time interval. A low visible light level camera provides quasi-continuous imaging of clouds at 1-km spatial resolution. Extended Earth coverage is achieved by step scanning the instrument field of view in a contiguous fashion across any desired portion of the visible Earth. The radiance spectra observed at each time step are transformed to high vertical resolution (1-2 km) temperature and water vapor mixing ratio profiles using rapid profile retrieval algorithms. These profiles are obtained on a 4km grid and then converted to relative humidity profiles. Images of the horizontal distribution of relative humidity for atmospheric levels, vertically separated by approximately 2 km, are constructed for each spatial scan. The sampling period will range from minutes to an hour, depending upon the spectral resolution and the area coverage selected for the measurement. Successive images of clouds and the relative humidity for each atmospheric level are then animated to reveal the motion of small-scale thermodynamic features of the atmosphere, providing a measure of the wind velocity distribution as a function of altitude 3,4 . The net result is a dense grid of temperature, moisture, and wind profiles which can also be used for atmospheric analyses and operational weather prediction. Feature tracking can be performed for mixing ratio profiles of O 3 and CO, derived from their spectral radiance features observed by the FTS instrument, providing a direct measure of the transport of these pollutant and greenhouse gases. It is the unique combination of the Fourier transform spectrometer and the large area format detector array (i.e., an imaging interferometer) and the geostationary satellite observation platform that enables the revolutionary wind profile and trace gas transport remote sensing measurements.