A posteriori clear-sky identification methods in solar irradiance time series: Review and preliminary validation using sky imagers

2019 ◽  
Vol 109 ◽  
pp. 412-427 ◽  
Author(s):  
Christian A. Gueymard ◽  
Jamie M. Bright ◽  
David Lingfors ◽  
Aron Habte ◽  
Manajit Sengupta
2010 ◽  
Vol 6 (S273) ◽  
pp. 89-95 ◽  
Author(s):  
A. F. Lanza

AbstractThe photospheric spot activity of some of the stars with transiting planets discovered by the CoRoT space experiment is reviewed. Their out-of-transit light modulations are fitted by a spot model previously tested with the total solar irradiance variations. This approach allows us to study the longitude distribution of the spotted area and its variations versus time during the five months of a typical CoRoT time series. The migration of the spots in longitude provides a lower limit for the surface differential rotation, while the variation of the total spotted area can be used to search for short-term cycles akin the solar Rieger cycles. The possible impact of a close-in giant planet on stellar activity is also discussed.


2015 ◽  
Vol 99 ◽  
pp. 196-207 ◽  
Author(s):  
Rusinek Rafal ◽  
Lajmert Pawel ◽  
Kecik Krzysztof ◽  
Kruszynski Bogdan ◽  
Warminski Jerzy

2021 ◽  
Author(s):  
Jean-Philippe Montillet ◽  
Wolfgang Finsterle ◽  
Werner Schmutz ◽  
Margit Haberreiter ◽  
Rok Sikonja

<p><span>Since the late 70’s, successive satellite missions have been monitoring the sun’s activity, recording total solar irradiance observations. These measurements are important to estimate the Earth’s energy imbalance, </span><span>i.e. the difference of energy absorbed and emitted by our planet. Climate modelers need the solar forcing time series in their models in order to study the influence of the Sun on the Earth’s climate. With this amount of TSI data, solar irradiance reconstruction models  can be better validated which can also improve studies looking at past climate reconstructions (e.g., Maunder minimum). V</span><span>arious algorithms have been proposed in the last decade to merge the various TSI measurements over the 40 years of recording period. We have developed a new statistical algorithm based on data fusion.  The stochastic noise processes of the measurements are modeled via a dual kernel including white and coloured noise.  We show our first results and compare it with previous releases (PMOD,ACRIM, ... ). </span></p>


1999 ◽  
Vol 34 (10) ◽  
pp. 1763-1774 ◽  
Author(s):  
José Leonaldo de Souza ◽  
João Francisco Escobedo ◽  
Maria Terezinha Trovareli Tornero

This paper describes the albedo (r) and estimates of net radiation and global solar irradiance for green beans crop (Phaseolus vulgaris L.), cultivated in greenhouse with cover of polyethylene and field conditions, in Botucatu, SP, Brazil (22º 54' S; 48º 27' W; 850 m). The solar global irradiance (Rg) and solar reflected radiation (Rr) were used to estimate the albedo through the ratio between Rr and Rg. The diurnal curves of albedo were obtained for days with clear sky and partially cloudy conditions, for different phenological stages of the crop. The albedo ranged with the solar elevation, the environment and the phenological stages. The cloudiness range have almost no influence on the albedo diurnal amount. The estimation of radiation were made by linear regression, using the global solar irradiance (Rg) and net short-waves radiation (Rc) as independent variables. All estimates of radiation showed better adjustment for specific phenological periods compared to the entire crop growing cycle. The net radiation in the greenhouse has been estimated by the global solar irradiance measured at field conditions.


1998 ◽  
Vol 25 (23) ◽  
pp. 4345-4348 ◽  
Author(s):  
C. Zerefos ◽  
C. Meleti ◽  
D. Balis ◽  
K. Tourpali ◽  
A. F. Bais
Keyword(s):  

2020 ◽  
Vol 161 ◽  
pp. 559-569 ◽  
Author(s):  
Camelia Liliana Moldovan ◽  
Radu Păltănea ◽  
Ion Visa

Sign in / Sign up

Export Citation Format

Share Document