Retrieval of cloud optical depth: synergies between whole sky imagers and radiative transfer modeling.

Caterina Peris-Ferrús; José Luís Gómez-Amo; Pedro C. Valdelomar; Francesco Scarlatti; Roberto Román; Claudia Emde; Maria Pilar Utrillas

doi:10.1117/12.2599586

12 September 2021 Retrieval of cloud optical depth: synergies between whole sky imagers and radiative transfer modeling.

Caterina Peris-Ferrús, José Luís Gómez-Amo, Pedro C. Valdelomar, Francesco Scarlatti, Roberto Román, Claudia Emde, Maria Pilar Utrillas

Author Affiliations +

Proceedings Volume 11859, Remote Sensing of Clouds and the Atmosphere XXVI; 118590W (2021) https://doi.org/10.1117/12.2599586
Event: SPIE Remote Sensing, 2021, Online Only

Conference Poster

Abstract

A commercial all-sky-camera is employed to derive a whole-sky product of Cloud Optical Depth. The methodology consists in a radiative closure combining measurements of the blue and red channels with libRadtran 1D monochromatic radiance simulations. Besides, a matrix of data quality Flags is obtained for every COD image. The data quality Flags indicate the reliability of the retrieval at each pixel, and gives information about the method to solve the radiance monochromatic ambivalence. In addition, the Flags product also indicates the presence of out-of-range radiances with respect to the RT simulations. Such out-of-range radiances are related to the neglection of horizontal radiation transport in the 1D plane-parallel approach. A set of around 2000 images during 2020 have been analyzed and COD has been obtained for each pixel. The COD shows values ranging from 0 to 130, with around 83% of the cases between 5 and 30. Our COD results have been validated using the zenith COD retrieval from AERONET. Our results present a very good agreement with AERONET cloud mode retrieval and show a correlation factor of 0.94 and a slope of 0.99 respectively.

Conference Presentation

Citation Download Citation

Caterina Peris-Ferrús, José Luís Gómez-Amo, Pedro C. Valdelomar, Francesco Scarlatti, Roberto Román, Claudia Emde, and Maria Pilar Utrillas "Retrieval of cloud optical depth: synergies between whole sky imagers and radiative transfer modeling.", Proc. SPIE 11859, Remote Sensing of Clouds and the Atmosphere XXVI, 118590W (12 September 2021); https://doi.org/10.1117/12.2599586

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available