Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 8 14 2008 10.5194/acp-8-3817-2008 http://www.atmos-chem-phys.net/8/3817/2008/ http://www.atmos-chem-phys.net/8/3817/2008/acp-8-3817-2008.html http://www.atmos-chem-phys.net/8/3817/2008/acp-8-3817-2008.pdf 3817 3826 2008-07-21 Technical Note: REFIR-PAD level 1 data analysis and performance characterization G. Bianchini gb@ifac.cnr.it L. Palchetti Istituto di Fisica Applicata "Nello Carrara" CNR-IFAC, Florence, Italy The outgoing long-wave radiation from the Earth's atmosphere in the far infrared spectral region is mostly unexplored, while is well recognized that the water vapour contribution to greenhouse trapping is dominant in this region. The Radiation Explorer in the Far InfraRed (REFIR) study has proven the feasibility of a space-borne Fourier transform spectrometer able to perform the measurement in the 100–1100 cm^−1 range with a resolution of 0.5 cm^−1. Following this work a prototype of the spectrometer named REFIR-PAD (Prototype for Applications and Development) has been developed to observe the atmospheric radiance from both ground-based sites and from stratospheric balloon platforms. In this work we describe the REFIR-PAD level 1 data analysis procedure, that, starting from raw instrumental data produces the calibrated atmospheric spectral radiance. Performances of the procedure are also described. Bianchini, G., Lanfranchi, M., and Cortesi, U.: Flight qualification of a diode laser for path difference determination of a high-resolution Fourier transform spectrometer, Appl. Optics, 39, 962–965, 2000. Bianchini, G., Cortesi, U., Palchetti, L., and Pascale, E.: Cosmic ray spikes localization and correction in FT spectrometer data, Infrared Phys. Techn., 43, 33–38, 2002. 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E., Leotin, J., Serio, C., Sutera, A., Bizzarri, B., Bonsignori, R., and Peskett, S.: Mission objectives and instrument requirements for the (REFIR) Radiation Explorer in the Far-InfraRed mission: an outline after the end of phase B0, in: Current Problems in Atmospheric Radiation, edited by: Smith, W. L. and Timofeyev, Y. M., Proc. of Int. Radiation Symp. (IRS) 2000, 567–570, 2001. Sinha, A. and Harries, J. E.: Water vapour and greenhouse trapping: The role of far infrared absorption, Geophys. Res. Lett., 22, 2147–2150, 1995.