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Unusual activity of the Sun during recent decades compared to the previous 11,000 years
A reconstruction of the sunspot number covering the past 11,400 years is reported, based on dendrochronologically dated radiocarbon concentrations, and it is pointed out that solar variability is unlikely to have been the dominant cause of the strong warming during the past three decades. Expand
Sunspots: An overview
Abstract. Sunspots are the most readily visible manifestations of solar magnetic field concentrations and of their interaction with the Sun's plasma. Although sunspots have been extensively studiedExpand
The 1.3-year and 156-day periodicities in sunspot data: Wavelet analysis suggests a common origin
Helioseismic data have revealed a 1.3-year periodicity in the solar rotation rate near the bottom of the solar convection zone. In order to test whether these rotation rate variations have aExpand
Reconstruction of solar total irradiance since 1700 from the surface magnetic flux
Context. Total solar irradiance changes by about 0.1% between solar activity maximum and minimum. Accurate measurements of this quantity are only available since 1978 and do not provide informationExpand
Climate and carbon-cycle variability over the last millennium
Abstract. A long-standing task in climate research has been to distinguish between anthropogenic climate change and natural climate variability. A prerequisite for fulfilling this task is theExpand
The AD775 cosmic event revisited: the Sun is to blame
Aims. Miyake et al. (2012, Nature, 486, 240, henceforth M12) recently reported, based on 14 C data, an extreme cosmic event in about AD775. Using a simple model, M12 claimed that the event was tooExpand
The 1.5 meter solar telescope GREGOR
The 1.5 m telescope GREGOR opens a new window to the understanding of solar small-scale magnetism. The first light instrumentation includes the Gregor Fabry Perot Interferometer (GFPI), a filterExpand
Small-scale solar magnetic fields: An overview
An overview is given of the observational and the theoretical methods used to investigate solar magnetic fields. It includes an introduction to the Stokes parameters, their radiative transfer in theExpand
Climate forcing reconstructions for use in PMIP simulations of the last millennium (v1.0)
Simulations of climate over the Last Millennium (850-1850 CE) have been incorporated into the third phase of the Paleoclimate Modelling Intercomparison Project (PMIP3). The drivers of climate overExpand
Toroidal versus poloidal magnetic fields in Sun-like stars: a rotation threshold
From a set of stellar spectropolarimetric observations, we report the detection of surface magnetic fields in a sample of four solar-type stars, namely HD 73350, HD 76151, HD 146233 (18 Sco) and HDExpand