Μελέτη της επίδρασης των αιωρούμενων σωματιδίων και των νεφών στην ηλιακή ακτινοβολία

• Main Authors: Vamvakas, Ioannis, Βαμβακάς, Ιωάννης
• Format: Doctoral or Postdoctoral Thesis
• Language: Greek
• Published: University of Patras 2020
• Subjects: Ηλιακή ακτινοβολία μικρού μήκους κύματος (SWR); Μοντέλο επίλυσης της εξίσωσης διάδοσης της ακτινοβολίας; Επιδράσεις των υδρατμών στην εξασθένιση της SWR; Αποδοτικότητα των υδρατμών στην εξασθένιση της SWR; Δείκτης αιθριότητας (Kt); Ηλιακή ζενίθια γωνία (sza); Αλγόριθμος εκτίμησης των αιωρημάτων; Εκτίμηση της SWR; Εκτίμηση της συνολικής; πυκνής και αραιής νεφοκάλυψης; Ενισχύσεις της SWR; Μέθοδοι προσαρμογής στην τοποθεσία; Βαθμονόμηση των θεωρητικών χρονοσειρών των αιωρημάτων; Κλιματικό σύστημα ταξινόμησης του Köppen-Geiger; Χρονοσειρές επανάλυσης; Δορυφορικές χρονοσειρές; Ρομποτικό δίκτυο των αιωρημάτων (AERONET); Στατιστική αξιολόγηση των ατμοσφαιρικών και ακτινομετρικών εκτιμήσεων; Shortwave solar irradiance (SWR); Radiative transfer model (RTM); Water vapor radiative effects (WVRE); Water vapor radiative efficiency (PWE); Clearness index; Solar zenith angle (sza); Estimation algorithm of aerosols; Estimation of SWR; Estimation of total; thick and thin cloud coverage; Enhancements of SWR; Site adaptation methods; Calibration of the aerosols theoretical time series; Köppen-Geiger (KG) climate classification system; Reanalysis time series; Satellite time series; Aerosol robotic network (AERONET); Statistical assessment of atmospheric and radiometric estimates; Φυσική; Φυσικές Επιστήμες; Εφαρμοσμένη φυσική; Γεωεπιστήμες και Επιστήμες Περιβάλλοντος; Μετεωρολογία και Επιστήμες της ατμόσφαιρας; Physical Sciences; Natural Sciences; Applied Physics; Earth and Related Environmental Sciences; Meteorology and Atmospheric Sciences; Aerosol Robotic Network
• Online Access: http://hdl.handle.net/10442/hedi/48906; https://doi.org/10.12681/eadd/48906

In the present doctoral thesis, the spatiotemporal effects of clouds, aerosols and integrated water vapor are examined, when the solar irradiance is transferred from the top of atmosphere to the Earth’s surface. The first chapter provides a brief description of the basic concepts of radiative transfer and the factors that affect the propagation of solar irradiance until the Earth’s surface. The main atmospheric parameters are examined based on their dominant types, optical properties, and mechanisms of scattering and absorption. Additionally, the Site Adaptation Methods for the correction of the uncertainties of atmospheric and radiometric estimates are presented briefly. These atmospheric and radiometric parameters derive from satellite sensor, reanalysis projects and their synergy with radiative transfer models. The second chapter provides a description of satellite sensor, reanalysis projects, atmospheric and radiometric stations, whose time series are used in this thesis, as well as the radiative transfer models for radiometric simulations. The third chapter identifies the dominant type of clouds and atmospheric conditions, which cause enhancing of the global shortwave solar irradiance (GHI). This type is cumulus mid and high-level clouds, while for solar zenith angles lower than 80°, 4% of total GHI measurements are considered as enhancements, with the values of GHI reaching up to 1420 W/m2. In the fourth chapter, the direct effect of aerosol and precipitable water (PW) optical properties are examined in the attenuation of GHI, and especially to the regions of North Africa and Middle East (MENA). According to the synergy of satellite time series from the two versions of MODIS (v6 and v6.1) and radiometric estimations from RTM, the GHI time series are estimated and statistically assessed against the ground-based measurements. The synergy of v.6.1 and RTM simulations provides better statistical results against the ground-based measurements for Middle-East sites and Tamanrasset (TAM), while for Adrar (ADR), ...