English
Related papers

Related papers: Reconstructed Total Solar Irradiance as a precurso…

200 papers

Although systematic measurements of the solar polar magnetic field exist only from mid 1970s, other proxies can be used to infer the polar field at earlier times. The observational data indicate a strong correlation between the polar field…

Astrophysics · Physics 2009-11-13 Jie Jiang , Piyali Chatterjee , Arnab Rai Choudhuri

Solar activity cycle varies in amplitude. The last Cycle 24 is the weakest in the past century. Sun's activity dominates Earth's space environment. The frequency and intensity of the Sun's activity are accordant with the solar cycle. Hence…

Solar and Stellar Astrophysics · Physics 2022-02-16 Wei Guo , Jie Jiang , Jing-Xiu Wang

The correlation between solar irradiance and the 11-year solar activity cycle is evident in the body of measurements made from space, which extend over the past four decades. Models relating variation in solar irradiance to photospheric…

Solar and Stellar Astrophysics · Physics 2015-07-07 K. L. Yeo , N. A. Krivova , S. K. Solanki

Solar activity has a cyclic nature with the ~11-year Schwabe cycle dominating its variability on the interannual timescale. However, solar cycles are significantly modulated in length, shape and magnitude, from near-spotless grand minima to…

Solar and Stellar Astrophysics · Physics 2023-03-29 Akash Biswas , Bidya Karak , Ilya Usoskin , Eckhard Weisshaar

We have reconstructed the sunspot group count, not by comparisons with other reconstructions and correcting those where they were deemed to be deficient, but by a re-assessment of original sources. The resulting series is a pure solar index…

Solar and Stellar Astrophysics · Physics 2016-03-23 Leif Svalgaard , Kennuth H. Schatten

The present paper reviews results derived from statistical studies on solar activity indices. The prolonged minimum phase of cycle 23 raised the question of peculiarities inherent in cycle 23. The most important solar activity index is the…

Solar and Stellar Astrophysics · Physics 2010-02-03 M. Temmer

Reliable prediction of the solar cycle is a formidable challenge, yet it is increasingly vital in our technology-dependent society as solar activity drives space weather. Various methods, including precursors, nonlinear curve fitting and…

Solar and Stellar Astrophysics · Physics 2026-04-20 Bidya Binay Karak

We use microwave imaging observations from the Nobeyama Radioheliograph at 17 GHz for long-term studies of solar activity. In particular, we use the polar and low-latitude brightness temperatures as proxies to the polar magnetic field and…

Solar and Stellar Astrophysics · Physics 2018-08-15 N. Gopalswamy , P. Makela , S. Yashiro , S. Akiyama

Changes in solar irradiance and in its spectral distribution are among the main natural drivers of the climate on Earth. However, irradiance measurements are only available for less than four decades, while assessment of solar influence on…

Solar and Stellar Astrophysics · Physics 2018-11-09 C. -J. Wu , N. A. Krivova , S. K. Solanki , I. G. Usoskin

Here we study the prediction of even and odd numbered sunspot cycles separately, thereby taking into account the Hale cyclicity of solar magnetism. We first show that the temporal evolution and shape of all sunspot cycles are extremely well…

Solar and Stellar Astrophysics · Physics 2023-09-11 Timo Asikainen , Jani Mantere

Context. Total solar irradiance allows for the use of the Sun as a star for studying observations of stellar light curves from recent space missions. Aims. We aim to study how the mid-range periodicity observed in solar activity indices…

Solar and Stellar Astrophysics · Physics 2021-09-29 Gurgenashvili , E. , Zaqarashvili , T. V. , Kukhianidze , V. , Reiners , A. , Oliver , R. , Lanza , A. F. , Reinhold , T

Aims. The Sun shows strong variability in its magnetic activity, from Grand minima to Grand maxima, but the nature of the variability is not fully understood, mostly because of the insufficient length of the directly observed solar activity…

Solar and Stellar Astrophysics · Physics 2014-02-24 I. G. Usoskin , G. Hulot , Y. Gallet , R. Roth , A. Licht , F. Joos , G. A. Kovaltsov , E. Thebault , A. Khokhlov

Total solar irradiance reconstructed between 1978 and 2003 using solar surface magnetic field distributions is compared with three composites of total solar irradiance measurements. A good correspondence is found with the total solar…

Solar and Stellar Astrophysics · Physics 2014-11-20 T. Wenzler , S. K. Solanki , N. A. Krivova

Knowledge of solar irradiance variability is critical to Earth's climate models and understanding the solar influence on Earth's climate. Direct solar irradiance measurements are only available since 1978. Reconstructions of past…

The use of different solar activity indices like sunspot numbers, sunspot areas, flare index, magnetic fields, etc., allows us to investigate the time evolution of some specific features of the solar activity and the underlying dynamo…

Solar and Stellar Astrophysics · Physics 2013-10-11 Stefano Sello

We study the origin of the predictive skill of some methods to forecast the strength of solar activity cycles. A simple flux transport model for the azimuthally averaged radial magnetic field at the solar surface is used, which contains a…

Astrophysics · Physics 2011-02-11 R. Cameron , M. Schuessler

It is suggested that the solar variability is due to the perturbed nature of the solar core and this variability is provided by the variability of the solar neutrino flux from the solar neutrino detectors i.e., Homestake, Superkamiokande,…

Astrophysics · Physics 2007-05-23 Probhas Raychaudhuri

Solar cycles are studied with the Version 2 monthly smoothed international sunspot number, the variations of which are found to be well represented by the modified logistic differential equation with four parameters: maximum cumulative…

Solar and Stellar Astrophysics · Physics 2018-12-19 G. Qin , S. -S. Wu

Reliable historical records of total solar irradiance (TSI) are needed for climate change attribution and research to assess the extent to which long-term variations in the Sun's radiant energy incident on the Earth may exacerbate (or…

Solar and Stellar Astrophysics · Physics 2016-04-13 G. Kopp , N. Krivova , J. Lean , C. J. Wu

Synoptic magnetograms provide us with knowledge about the evolution of magnetic fields on the solar surface and present important information for forecasting future solar activity. In this work, poloidal and toroidal magnetic field…

Solar and Stellar Astrophysics · Physics 2020-02-19 Irina N. Kitiashvili