title: Multichannel radiometer calibration: a new approach.
abstract: The error in irradiance measured with Sun-calibrated multichannel radiometers may be large when the solar zenith angle (SZA) increases. This could be particularly detrimental in radiometers installed at mid and high latitudes, where SZAs at noon are larger than 50 degrees during part of the year. When a multiregressive methodology, including the total ozone column and SZA, was applied in the calculation of the calibration constant, an important improvement was observed. By combining two different equations, an improvement was obtained at almost all the SZAs in the calibration. An independent test that compared the irradiance of a multichannel instrument and a spectroradiometer installed in Ushuaia, Argentina, was used to confirm the results.
authors.affiliation: Centro Austral de Investigaciones Científicas, Consejo Nacional de Investigaciones Científicas y Técnicas, B. Houssay 200, 9410 Ushuaia, Argentina. subediaz@speedy.com.ar
authors.forename: Susana
authors.initials: S
authors.lastname: Diaz
authors.forename: Charles R
authors.initials: CR
authors.lastname: Booth
authors.forename: Roy
authors.initials: R
authors.lastname: Armstrong
authors.forename: Claudio
authors.initials: C
authors.lastname: Brunat
authors.forename: Sergio
authors.initials: S
authors.lastname: Cabrera
authors.forename: Carolina
authors.initials: C
authors.lastname: Camilion
authors.forename: Claudio
authors.initials: C
authors.lastname: Casiccia
authors.forename: Guillermo
authors.initials: G
authors.lastname: Deferrari
authors.forename: Humberto
authors.initials: H
authors.lastname: Fuenzalida
authors.forename: Charlotte
authors.initials: C
authors.lastname: Lovengreen
authors.forename: Alejandro
authors.initials: A
authors.lastname: Paladini
authors.forename: Jorge
authors.initials: J
authors.lastname: Pedroni
authors.forename: Alejandro
authors.initials: A
authors.lastname: Rosales
authors.forename: Horacio
authors.initials: H
authors.lastname: Zagarese
authors.forename: Maria
authors.initials: M
authors.lastname: Vernet