title: Synchronized Northern Hemisphere climate change and solar magnetic cycles during the Maunder Minimum.
abstract: The Maunder Minimum (A.D. 1645-1715) is a useful period to investigate possible sun-climate linkages as sunspots became exceedingly rare and the characteristics of solar cycles were different from those of today. Here, we report annual variations in the oxygen isotopic composition (δ(18)O) of tree-ring cellulose in central Japan during the Maunder Minimum. We were able to explore possible sun-climate connections through high-temporal resolution solar activity (radiocarbon contents; Δ(14)C) and climate (δ(18)O) isotope records derived from annual tree rings. The tree-ring δ(18)O record in Japan shows distinct negative δ(18)O spikes (wetter rainy seasons) coinciding with rapid cooling in Greenland and with decreases in Northern Hemisphere mean temperature at around minima of decadal solar cycles. We have determined that the climate signals in all three records strongly correlate with changes in the polarity of solar dipole magnetic field, suggesting a causal link to galactic cosmic rays (GCRs). These findings are further supported by a comparison between the interannual patterns of tree-ring δ(18)O record and the GCR flux reconstructed by an ice-core (10)Be record. Therefore, the variation of GCR flux associated with the multidecadal cycles of solar magnetic field seem to be causally related to the significant and widespread climate changes at least during the Maunder Minimum.
authors.affiliation: Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 275-8564, Japan.
authors.forename: Yasuhiko T
authors.initials: YT
authors.lastname: Yamaguchi
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Yokoyama
authors.forename: Hiroko
authors.initials: H
authors.lastname: Miyahara
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Sho
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakatsuka
mesh_terms: D028203:Cedrus; D002482:Cellulose; D057231:Climate Change; D049670:History, 17th Century; D049671:History, 18th Century; D006813:Humidity; D007564:Japan; D008280:Magnetics; D008685:Meteorological Concepts; D010103:Oxygen Isotopes; D019445:Solar Activity
chemical_list: D010103:Oxygen Isotopes; D002482:Cellulose