@misc{10481/81991,
year = {2023},
url = {https://hdl.handle.net/10481/81991},
abstract = {A new method to estimate aerosol radiative forcing (ARF) on photosynthetically active radiation (PAR) is proposed
using as input only the solar position and global irradiance measurements, available in many radiometric
stations worldwide. The main contribution of this work is the proposal of a new and simple tool (max-kt method)
based in the parameterization of the envelope of the relationship between clearness index (kt) and the solar
position. To this aim, a 1-year database (2020) of cloud-free data acquired in a Southwest Mediterranean site was
used for the proposal and two more years (2017 and 2018) were used to extend the results. The ARF values
retrieved using the new method were compared with estimates calculated by two physical models widely
employed in the literature, such as the SBDART (Santa Barbara DISORT Atmospheric Radiative Transfer model)
and an improved version of the CPCR2 (Code for Physical Computation of Radiation, 2 bands) model. The new
method provided ARF values of the order of those provided by these physical models, especially with the
SBDART model, confirming the validity of this new method. An ARF seasonal pattern was found with higher
values in summer, (-30,7 ± 9,0) Wm- 2 in August during 2017, (- 40,1 ± 11,8) Wm- 2 in June during 2018 and
(- 28,8 ± 7,7) Wm- 2 in July during 2020 and minimum values in winter, (- 8,1 ± 5,1) Wm- 2 in January during
2017, (- 5,7 ± 5,8) Wm- 2 in December during 2018 and (- 7,8 ± 5,4) Wm- 2 in December during 2020.
Moreover, a dependence on solar zenith angle (θz) was detected excepting during the year 2018, increasing ARF
absolute values at θz from 0◦ to 45◦-60◦ and decreasing to zero for the Sun near the horizon. This technique is
very useful due to the difficulty of knowing all the inputs requested by the physical models.},
organization = {Spanish Ministry of Economy and Competitiveness through projects CGL2017-90884-REDT, PID2020-
120015RB-I00, PID2020-117825GB-C21, PID2020-117825GB-C22 and PID2021-128008OB-I00, by the Andalusia Regional Government, University of Granada and FEDER funds through project B-RNM-524- UGR20, A-RNM-430-UGR20, P20-00136 and P18-RT-3820},
publisher = {Elsevier},
keywords = {Aerosols},
keywords = {Photosynthetically active radiation},
keywords = {Radiative forcing},
title = {A new method to estimate aerosol radiative forcing on photosynthetically active radiation},
doi = {https://doi.org/10.1016/j.atmosres.2023.106819},
author = {Foyo Moreno, Inmaculada and Lozano, Ismael L. and Alados-Arboledas, Inmaculada and Guerrero Rascado, Juan Luis},
}