The past two decades have witnessed significant changes in our knowledge of long-term solar and solar wind activity. The sunspot number time series (1700-present) developed by Rudolf Wolf during the second half of the 19th century was revised and extended by the group sunspot number series (1610–1995) of Hoyt and Schatten during the 1990s. The group sunspot number is significantly lower than the Wolf series before ∼1885. An effort from 2011–2015 to understand and remove differences between these two series via a series of workshops had the unintended consequence of prompting several alternative constructions of the sunspot number. Thus it has been necessary to expand and extend the sunspot number reconciliation process. On the solar wind side, after a decade of controversy, an ISSI International Team used geomagnetic and sunspot data to obtain a high-confidence time series of the solar wind magnetic field strength (B$B$) from 1750-present that can be compared with two independent long-term (> ∼600 year) series of annual B$B$-values based on cosmogenic nuclides. In this paper, we trace the twists and turns leading to our current understanding of long-term solar and solar wind activity.

中文翻译：

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太阳黑子数和太阳风 B$B$ 时间序列的演变

在过去的二十年里，我们对长期太阳和太阳风活动的了解发生了重大变化。19 世纪下半叶鲁道夫·沃尔夫 (Rudolf Wolf) 开发的太阳黑子数时间序列 (1700 年至今) 在 1990 年代由霍伊特 (Hoyt) 和沙滕 (Schatten) 的太阳黑子数序列 (1610–1995) 修订和扩展。群太阳黑子数明显低于 ∼1885 年之前的 Wolf 系列。从 2011 年到 2015 年，通过一系列研讨会来理解和消除这两个系列之间的差异的努力产生了意想不到的结果，促使了太阳黑子数的几种替代结构。因此，有必要扩大和延长太阳黑子数量协调过程。在太阳风方面，经过十年的争论，ISSI 国际团队使用地磁和太阳黑子数据获得了 1750 年至今的太阳风磁场强度 (B$B$) 的高置信度时间序列，可以与两个独立的长期（>~600 年）进行比较基于宇宙成因核素的一系列年度 B$B$ 值。在本文中，我们追溯了导致我们目前对长期太阳和太阳风活动的理解的曲折。