J/A+A/562/L10ivo://CDS.VizieR/J/A+A/562/L10doi:10.26093/cds/vizier.35629010CDSUsoskin I.G.Hulot G.Gallet Y.Roth R.Licht A.Joos F.,Kovaltsov G.A.Thebault E.Khokhlov A.2017-06-20T13:16:11Z2014-02-20T12:58:10ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frthe-sunThe Sun shows a large variability in its magnetic activity, from Grand minima to Grand maxima, but the nature of the variability is not fully understood, mostly because of an insufficient length of the directly observed solar activity records and of uncertainties related to long-term reconstructions. Here we present a new adjustment-free reconstruction of solar activity over three millennia and study its different modes. We present a new adjustment-free, physical reconstruction of solar activity over the past three millennia, using the latest verified carbon cycle, ^14^C production and archeomagnetic field models. This great improvement allows us to study different modes of solar activity at unprecedented level of details. The distribution of solar activity is clearly bi-modal implying the existence of distinct modes of activity. The main regular activity mode corresponds to moderate activity varying in a relatively narrow band between sunspot number 20 and 67. The existence of a separate Grand minimum mode with reduced solar activity, which cannot be explained by random fluctuations of the regular mode, is confirmed at a high confidence level. The possible existence of a separate Grand maximum mode is also suggested, but the statistics is too low for a confident conclusion to be reached. The Sun is shown to operate in distinct modes - a main general mode, a Grand minimum mode corresponding to an inactive Sun, and a possible Grand maximum mode corresponding to an unusually active Sun. These results provide important constraints for both dynamo models of Sun-like stars and investigations of possible solar influence on Earth's climate.2014A&A...562L..10Uhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/562/L10CatalogResearchIsServedByTAP VizieR generic servicerelated-toVI/138 : Sunspots catalogues, 1853-1870 (Casas+, 2013)J/A+A/531/A6 : Evolution of solar irradiance during Holocene (Vieira+, 2011)J/A+A/390/707 : Hemispheric Sunspot Numbers 1975-2000 (Temmer+, 2002)J/A+A/447/735 : Hemispheric Sunspot Numbers 1945-2004 (Temmer+, 2006)J/A+AS/110/351 : Sun observations in 1992 (Sanchez+, 1995)J/A+AS/106/327 : Observations of the Sun during 1993 at Santiago (Noel 1994)J/A+AS/113/131 : Observations of the Sun during 1994 (Noel, 1995)J/A+AS/132/195 : Astrolabe observations of the Sun in 1995-1997 (Noel 1998)J/A+AS/102/11 : Astrolabe observations of the Sun in 1990-1992 (Noel 1993)J/A+A/375/614 : Astrolabe observations of the Sun in 1990-2000 (Noel, 2001)J/A+A/309/655 : Solar chromospheric activity (HeI 10830A) (Shcherbakov+, 1996)J/A+A/313/949 : Solar chromospheric structures. II. (Bocchialini+, 1996)J/A+A/375/591 : SUMER Spectral Atlas of Solar Disk Features (Curdt+, 2001)J/A+A/422/337 : Solar EUV Post-Eruptive Arcades (Tripathi+, 2004)J/A+A/423/1109 : Center-to-limb variation of quiet Sun (Allende+, 2004)J/ApJ/709/1238 : Solar Coronal Mass Ejection (Yeates+, 2010)J/A+A/539/A13 : Solar bipolar magnetic fields (Yamamoto, 2012)J/A+A/552/A114 : Sun chromospheric CaII-HK emission (Shapiro+, 2013)J/A+A/555/A123 : 3D-MHD model of a solar active region corona (Bourdin+, 2013)J/A+AS/119/489 : Solar Type II Radio Bursts, 1990.09 - 1993.12 (Mann+ 1996)J/A+AS/130/233 : WATCH Solar X-Ray Burst Catalogue (Crosby+ 1998)J/ApJ/710/L58 : Coronal type II radio bursts in 2002 (Lobzin+, 2010)J/ApJ/747/L41 : Solar flares probabilities (Bloomfield+, 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/562/L10https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/562/L10http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/562/L10https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/562/L10https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/562/L10http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/562/L10GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/562/L10/activityDecadal solar activity:recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintYear[-1145/1945] Central year of the decadal interval (-BC/AD)yrtime.epochintSNDecadal sunspot number (mean)meta.number;phys.atmol.numberfloatb_SNDecadal sunspot number (lower c.i. 95% bound)meta.number;phys.atmol.number;stat.minfloatB_SNDecadal sunspot number (upper c.i. 95% bound)meta.number;phys.atmol.number;stat.maxfloatphiDecadal modulation potential (mean)MVsrc.var.indexintb_phiDecadal mod. potential (lower c.i. 95% bound)MVsrc.var.index;stat.minintB_phiDecadal mod. potential (upper c.i. 95% bound)MVsrc.var.index;stat.maxint