Aerosols optical thickness estimation from MODIS sensor images over Perú (2004-2005)

In the present work we estimate the aerosols optical thickness (AOT) in the wavelength of 0.55µm using the mod021km - level 1B Calibrated Radiances - 1km images as input of the SBDART radiative transfer model [1]. The study area is Peru in the geographic latitudes 0 to 20°S and the geographic longit...

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Detalhes bibliográficos
Autores: Cholan, E., Rojas, J., Willems, B. L., Ocola, L. C.
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2017
País:Perú
Recursos:Universidad Nacional Mayor de San Marcos
Repositório:Revistas - Universidad Nacional Mayor de San Marcos
Idioma:espanhol
OAI Identifier:oai:revistasinvestigacion.unmsm.edu.pe:article/13557
Acesso em linha:https://revistasinvestigacion.unmsm.edu.pe/index.php/fisica/article/view/13557
Access Level:Acceso aberto
Palavra-chave:SBDART
MODIS
aerosoles
espesor óptico
AERONET
aerosols
optical thickness
Descrição
Resumo:In the present work we estimate the aerosols optical thickness (AOT) in the wavelength of 0.55µm using the mod021km - level 1B Calibrated Radiances - 1km images as input of the SBDART radiative transfer model [1]. The study area is Peru in the geographic latitudes 0 to 20°S and the geographic longitudes of 82 to 68°O. The SBDART model simulates the radiative transfer in the atmosphere (scattering, absorption, emission, etc.), estimating the irradiance in the top of the atmosphere and on the Earth surface. The two-stream and Eddington approximations are used to solve the radiative transfer equation, considering a parallel plane atmosphere. This model generate equations defining the AOT of 0.55µm as a function of the reflectance at the top of the atmosphere (TOA) for the band 1 at 0.66µm of the MODIS sensor.The 0.55 µm AOT estimated by the SBDART model was verify with the 0.55µm AOT data measured in-situ from an AERONET network station located in Rio Branco, Brazil, for the both year 2004 and 2005.The station is located at latitude 9.954°S and longitude 67.869°O. The dispersion dataplot of the time series of both AOT showed a (not) significant correlation of 0.99 (0.06) for the year 2004 and 2005.Also, was verify the AOT obtained from the MODIS images (MOD04_L2) with the AOT estimated by the SBDART model, the scatter plot of the time series of both AOT showed a significant correlation of 0.99 for both year 2004 and 2005, while the verification of the AOT from the MODIS images (MOD04_L2) with the 0.55µm AOT data in-situ from Rio Branco, show in the dispersion dataplot of the time series an (not) significant correlation of 0.98 (0.02) for the year 2004 and 2005. The SBDART model used for estimating the AOT is limited to the Central and Southern part of Peru, due to its geographic location, meteorological conditions, atmospheric circulation and optical properties of aerosols. Keywords: SBDART, MODIS, aerosols, optical thickness, AERONET.