Abstract
Based on the analysis of solar radiation and meteorological parameters measured at a subtropical forest in China during 2013–2016, a new empirical model of global solar irradiance has been developed. It can calculate global solar irradiance at the ground and at the top of the atmosphere (TOA); both are in agreement with the observations. This model is used to calculate the extinction of global solar irradiance in the atmosphere and the contributions from absorbing and scattering substances. The loss of global solar irradiance is dominated by absorbing and absorbing substances. The results show clear seasonal and interannual variations during the observation period. Sensitivity analysis indicates that global solar irradiance is more sensitive to changes in scattering, quantified by the S/G factor (S and G are diffuse and global solar radiation, respectively), than to changes in absorption. The relationships between the extinction factor (AF) of G and S/G and between the AF and the aerosol optical depth (AOD) are determined and used to estimate S/G and the AOD from the measured AF. This empirical model is applied to calculate the albedos at the TOA and the ground. This empirical model is useful to study global solar radiation and the energy–atmosphere interactions.
Highlights
Solar radiation in the atmosphere interacts with molecules and particles
Global solar irradiance was more sensitive to changes in the scattering factor than in the absorbing factor in this subtropical Pinus forest, reflecting that changes in scattering GLPs, e.g., aerosols produced from biogenic volatile organic compounds (BVOCs) oxidation with NOx and O3, have a larger effect on global solar radiation at the ground than changes in absorbing GLPs, for the same changing rates of E and S/G
The decrease of global solar radiation at the ground is associated with energy losses: (1) absorption and scattering caused by GLP changes, including aerosols, clouds, gases, water vapor, and (2) the increase of reflection at the TOA
Summary
Solar radiation in the atmosphere interacts with molecules and particles. It provides energy that drives the movement of air, convection, and advection. The objectives and main novelties of this study are to develop a new empirical model of global solar radiation based on the analysis of high-quality observational data under optimal atmospheric conditions and to further study (1) global solar radiation (hourly, daily, monthly, yearly) near the surface and at the TOA; (2) the extinction of global solar radiation in the atmosphere, associated with the total atmospheric absorbing and scattering substances (in the atmospheric column); (3) the albedo at the TOA and at the surface; and (4) relationships between both absorption and scattering and meteorological variables (temperature, relative humidity, and water vapor pressure) The achievement of these objectives is expected to improve our understanding of the basic processes and mechanisms associated with atmospheric radiation and its effect on regional climate and climate change. This data quality corresponds to that using the observed solar radiation data in the range of 0–1.2 times the extraterrestrial radiation by Bilbao et al [21]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
