A STUDY OF VARIATION OF THE 11-YR SOLAR CYCLE BEFORE THE ONSET OF THE SPOERER MINIMUM BASED ON ANNUALLY MEASURED 14C CONTENT IN TREE RINGS

被引：11

作者：

Moriya, Toru ^{[1
]}

Miyahara, Hiroko ^{[2
]}

Ohyama, Motonari ^{[3
]}

Hakozaki, Masataka ^{[4
]}

Takeyama, Mirei ^{[1
]}

Sakurai, Hiroshi ^{[5
]}

Tokanai, Fuyuki ^{[1
,5
]}

机构：

[1] Yamagata Univ, Ctr Accelerator Mass Spectrometry, Yamagata 9993101, Japan

[2] Musashino Art Univ, Museum Carriers, Humanities & Sci, Tokyo 1878505, Japan

[3] Tohoku Univ, Bot Gardens, Sendai, Miyagi 9800862, Japan

[4] Natl Museum Japanese Hist, Sakura, Chiba 2858502, Japan

[5] Yamagata Univ, Fac Sci, Yamagata 9908560, Japan

来源：

RADIOCARBON | 2019年 / 61卷 / 06期

关键词：

11-yr solar cycle; Spoerer Minimum; YU-AMS; FLUX TRANSPORT DYNAMO; GRAND MINIMA; RADIOCARBON; CALIBRATION; CYCLICITY;

D O I：

10.1017/RDC.2019.123

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

Proxy-based observations of solar activity in the past have revealed long-term variations, such as the Gleissberg cycle (similar to 88 yr), de Vries cycle (similar to 200 yr), and the Hallstatt cycle (similar to 2000 yr). Such long-term variations of solar activity sometimes cause the disappearance of sunspots for several decades. Currently, solar activity is becoming weaker, and there is a possibility that another long-term sunspot minimum could occur. However, the detailed mechanism of the weakening in solar activity is unknown, and the prediction of solar activity is ambiguous. In this study, we investigate the transitions of solar cycle length before the onset of the Spoerer Minimum, the longest grand minimum in the past 2000 yr. We measured the C-14 content in an asunaro tree (Thujopsis dolabrata) excavated at Shimokita Peninsula from 1368-1420 CE using the compact AMS system at Yamagata University. It is found that the solar cycle lengthened to be 14-16 yr from 2 cycles before the onset of the Spoerer Minimum.

引用

页码：1749 / 1754

页数：6