author = "Pinto, Ciebele Teixeira and Ponzoni, Fl{\'a}vio Jorge and 
                         Barrientos, C. and Mattar, C. and Santamar{\'{\i}}a-Artigas, A. 
                         and Castro, Ruy M.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Chile Air Force} and 
                         {Instituto de Estudos Avan{\c{c}}ados (IEAv)} and {Instituto de 
                         Estudos Avan{\c{c}}ados (IEAv)} and {Instituto de Estudos 
                         Avan{\c{c}}ados (IEAv)}",
                title = "Spectral and atmospheric characterization of a site at Atacama 
                         Desert for earth observation sensor calibration",
              journal = "IEEE Geoscience and Remote Sensing Letters",
                 year = "2015",
               volume = "12",
               number = "11",
                pages = "2227--2231",
                month = "Nov.",
             keywords = "Aerosols, Atmospheric measurements, Calibration, Earth, Optical 
                         sensors, Optical variables control, Remote sensing.",
             abstract = "The application of Earth observation sensor data in quantitative 
                         approaches calls on the conversion of original digital numbers to 
                         radiometric quantities such as radiance or reflectance. This 
                         conversion depends on the sensor absolute calibration. One of the 
                         postlaunch methods adopted to calibrate orbital sensors is the 
                         reflectance-based approach. According to this method, a reference 
                         surface with specifics characteristics is required. The main 
                         objective of this work is to evaluate the suitability of a 
                         specific surface located at Atacama Desert in Chile to be used as 
                         a reference surface for calibration of Earth observation sensor 
                         purposes. A field campaign was carried out from August 19 to 22, 
                         2014, when radiometric measurements were performed to spectrally 
                         characterize the reference surface and to evaluate the atmospheric 
                         characteristics of the study area. The average reference surface 
                         reflectance factor in the spectral region from 350 to 2500 nm 
                         ranged from 0.1 to 0.3, and its spatial uniformity was within 
                         2%-4%. The amount of atmospheric aerosols was low, with an aerosol 
                         optical depth at 550 nm between 0.08 and 0.11 during the fieldwork 
                         period. The climate is hyperarid, and the water column abundance 
                         was lower than 0.43 g/cm2. The results demonstrated that a 
                         reference surface at Atacama Desert could be effectively used for 
                         calibration of either airborne or orbital electrooptical sensors, 
                         providing an excellent surface in South America.",
                  doi = "10.1109/LGRS.2015.2460454",
                  url = "http://dx.doi.org/10.1109/LGRS.2015.2460454",
                 issn = "1545-598X",
             language = "en",
        urlaccessdate = "24 jan. 2021"