Abstract
The characterization of a charged-coupled device (CCD) spectrograph developed at the Laboratory of Atmospheric Physics, Thessaloniki is presented. The absolute sensitivity of the instrument for direct irradiance and sky radiance measurements was determined, respectively, with an uncertainty of 4.4% and 6.6% in the UV-B, and 3% and 6% in the UV-A, visible and near-infrared (NIR) wavelength ranges. The overall uncertainty associated with the direct irradiance and the sky radiance measurements is, respectively, of the order of 5% and 7% in the UV-B, increasing to 10% for low signals [e.g., at solar zenith angles (SZAs) larger than ], and 4% and 6% in the UV-A, visible, and NIR. Direct solar spectral irradiance measurements from an independently calibrated spectroradiometer (Bentham DTM 300) were compared with the corresponding CCD measurements. Their agreement in the wavelength range of is within (for SZA between and ). Aerosol optical depth (AOD) derived by the two instruments using direct Sun spectra and by a collocated Cimel sunphotometer [Aerosol Robotic network (AERONET)] agree to within in the range of . Significant correlation coefficients with a maximum of 0.99 in the range of and a minimum of 0.90 at were found between synchronous AOD measurements with the Bentham and the Cimel instruments.
© 2008 Optical Society of America
Full Article | PDF ArticleMore Like This
Zhengqiang Li, Luc Blarel, Thierry Podvin, Philippe Goloub, Jean-Pierre Buis, and Jean-Philippe Morel
Appl. Opt. 47(10) 1368-1377 (2008)
Stelios Kazadzis, Alkiviadis Bais, Natalia Kouremeti, Evangelos Gerasopoulos, Katerina Garane, Mario Blumthaler, Barbara Schallhart, and Alexander Cede
Appl. Opt. 44(9) 1681-1690 (2005)
Alcide di Sarra, Daniele Fua, Marco Cacciani, Tatiana Di Iorio, Patrick Disterhoft, Daniela Meloni, Francesco Monteleone, Salvatore Piacentino, and Damiano Sferlazzo
Appl. Opt. 47(33) 6142-6150 (2008)