The Ratio Between the Number of Sunspot and the Number of Sunspot Groups

Data from three solar observatories (Learmonth, Holloman, and San Vito) are used to study the variations in the average number of sunspots per sunspot group. It is found that the different types of sunspot groups and the number of sunspots in these groups have different solar cycle and cycle to cycle variations. The varying ratio between the average number of sunspots and the number of sunspot groups is shown to be a real feature and not a result of changing observational instruments, observers’ experience, calculation schemes, etc., and is a result of variations in the solar magnetic fields. Therefore, the attempts to minimize the discrepancies between the sunspot number and sunspot group series are not justified, and lead to the loss of important information about the variability of the solar dynamo.     

Features of Slow Sunspot Dissipation

Geomagnetism and Aeronomy - According to a model of sunspot dissipation through a thin boundary layer between the sunspot magnetic flux tube and the surrounding medium, the rate of decrease in the...     

Influence of Supergranulation on the Properties of Sunspot Bipoles

Geomagnetism and Aeronomy - The properties of solar bipoles based on data from magnetic field observations at Mount Wilson Observatory during the period of 1917–2016 are considered. Special...     

The Waldmeier Effect for Two Sunspot Populations

Geomagnetism and Aeronomy - This paper continues our studies in which we showed that sunspot groups form two populations differing by physical properties—populations of small and large...     

The Gnevyshev-Ohl Rule and Two Sunspot Group Populations

Geomagnetism and Aeronomy - This work continues the study of the two sunspot group populations' properties discovered earlier (Nagovitsyn et al., 2009; Nagovitsyn et al., 2012; Nagovitsyn et...     

Sunspot Activity and Coronal Holes during the Declining Phase of Cycle 24

Geomagnetism and Aeronomy - The dynamics of coronal holes (CHs) during the declining phase of solar cycle 24 is studied based on observational data from the Atmospheric Imaging Assembly (AIA), the...     

Relationship of the Magnetic-Field Strength and the Brightness of the Sunspot Umbra and the Center of a Facular Knot

Geomagnetism and Aeronomy - Two main features define a sunspot as an object: a strong magnetic field and a low umbra temperature. The same can be said about a facular knot, in the center of which...     

Sunspot numbers and area-weighted united states monthly temperature and precipitation

Spectral analyses were made of derived area-index series of areas subject to extreme temperatures and precipitation as well as cross-spectral analyses of the area-index series with double sunspot cycle (Zurich) numbers. Superposed epoch analyses also were made of area-index series versus various double-sunspot cycle phases. Area series for wet and dry Junes, warm Junes, defined June drought, and warm Januaries all show statistically significant double sunspot cycle (21 year) periodicities. The 21-year cycle of above-normal June precipitation is most striking and has not received previous recognition.Journal Paper No. J-10007 of the Iowa Agric. and Home Econ. Exp. Stn., Iowa State University, Ames, IA, 50011, Project 2397.     

SDO Data Artifacts and Anticorrelation of Oscillations in the Sunspot Magnetic Field and Umbral Area

Geomagnetism and Aeronomy - The paper considers a special class of artifacts that appears in the useful signal when the source moves along a discrete matrix of the receiver. A parasitic component...     

The Maunder minimum as a secular minimum with non-stopped Sunspot cyclicity

One of the most enigmatic features of the solar history is the Maunder minimum (1645–1715). We compare the scatter of amplitudes of the 11-year cycles, according to the new Sunspot Number and Sunspot Group series version 2.0, along with scenario of the Maunder minimum as a period with non-stopped cyclicity. We demonstrate that both amplitude and duration of cycles after the Gleissberg and Maunder minima are similar. Moreover, times of minima and maxima of cycles in the course the Maunder minimum coincide with those during the Gleissberg one, indicating a secular variation. Usefulness of the proxy data within the Maunder minimum is discussed. The scatter of amplitudes and duration of the Schwabe cycles in the past is argued to be comparable with those in the modern epoch.     

Anomalies of Shape of 11-year Solar Cycle in Sunspot Number Series

Geomagnetism and Aeronomy - The shape of the 11-year cycle of solar activity can be described by a set of parameters that include its amplitude, the lengths of the ascending and descending branches...     

Shape of the 11-Year Cycle of Solar Activity and the Evolution of Latitude Characteristics of the Sunspot Distribution

Geomagnetism and Aeronomy - The solar activity index and parameters of the spatial distribution of sunspots are known to be related. Using these relationships, we propose interrelated...     

太阳黑子活动及地球自转对江苏及邻区地震的影响分析

根据太阳黑子活动和地球自转数据,分析了两者对江苏及邻区中强地震的影响.结果显示:太阳黑子活动下降段及地球自转加速度上升和转折段有利于该地区中强地震的发生;且在太阳黑子活动的下降时间内,每一个地球自转加速度的转折都会使得该地区中小地震频度增高:另外,从幅相法统计以及太阳黑子活动预测数据来看,2012年2月以后江苏及邻区的...     

Evolution of Sunspot Magnetic Fields from the Measurements at the BST-2 Telescope of the Crimean Astronomical Observatory in Solar Cycle 24

Geomagnetism and Aeronomy - The evolution of the averaged values of the sunspot magnetic fields with a strength of ≥1500 G has been studied based on long-term spectral observations of the...     

Sunspot indices characterizing the 11-year cycle as a whole and their relationship to the analogous indices of geomagnetic activity

Summary Sunspot indices characterizing the 11-year cycle as a whole were determined on the basis of Wolf's sunspot numbers and their total area as well as on the basis of the primary physically indices of the spot-generating activity of the Sun.Their interrelationship is shown and their relationship to the indices of geomagnetic activity aa and C_i is examined. It is shown that under high solar activity a certain saturation of the Earth's magnetosphere occurs and that the variations of geomagnetic activity correlate with the variations of the global sunspot indices (Wolf number and total area) but correlate but slightly with the primary physically sunspot indices.

---

u u n¶rt;;u nm u uuu nu u¶rt;; nmaoam ¶rt;;mmu q, n¶rt;; u¶rt;;u nm, aamuu -mu u . aaa u aua u u u mu u¶rt;;a ¶rt;;a¶rt;;um amumu aa u _i. aa, m nu amumu mynam am aum u m auauu ¶rt;;a¶rt;;umo amumu um auauau ¶rt;; u¶rt;; nm (u a, aa na¶rt;), a um uuu nuu u¶rt;u nm.

     

Efficiency of Ionospheric Model Correction by Vertical-Incidence Sounding Data from an Ionosonde during Low Sunspot Activity

Geomagnetism and Aeronomy - Numerical values of the criteria for the efficiency of the determination of the critical frequency of the F2 layer of ionosphere over European Russia are calculated with...     

Sunspot groups with high flare activity: Specific features of magnetic configuration,morphology, and dynamics

Specific features of the magnetic configuration, morphological structure, dynamics, and evolution of sunspot groups of the current (24th) cycle of solar activity with high flare activity are considered. The gradients of longitudinal magnetic fields at places of δ-configuration are calculated. The main finding is a time delay of 24–30 h between the time when the magnetic field gradient reaches a critical level of 0.1 G/km and the time when the first of powerful flares occurs in the active region. The study is based on data from the SDO and GOES-15 spacecrafts and ground-based solar telescopes (TST-2 at the Crimean Astrophysical Observatory of the Russian Academy of Sciences and the 150-foot telescope at the Mount Wilson Observatory).     

Quasiperiodic Sunspot Oscillations on Timescales from Tens to Hundreds of Minutes: Groundbased Optical Observations (a Review)

Over the last decade, a number of papers discussing long-period sunspot oscillations—with periods of tens and hundreds of minutes—have appeared. These studies are mainly based on the data of space probes. Despite the many possibilities in the time resolution and the absence of a distorting effect of the atmosphere, such studies face some artifacts connected with the pixel structure of an image (Nagovitsyn and Rybak, 2014); the existence of this phenomenon itself is still under discussion. On the other hand, starting already in the 1970s, long-period oscillations were studied by groundbased methods, including optical investigations after the mid-1980s. Since the papers containing the results of this research were mainly published in the Russian literature, which is not readily available for a wide range of specialists (mostly, in the Solnechnye Dannye bulletin or the proceedings of all-Russia conferences), they have been lost. The objective of this review is to recall these studies and their results and to combine the earlier findings with up-to-date ones.     

月球节点和太阳黑子活动与马边地区地震活动关系探讨

本文对月球每隔18．6年循环达其运行轨道最北节点N周期位置，和太阳黑子活动周期位相与马边－雷波－屏山区域地震活动的关系进行研究分析，发现，本区发生M≥3．6，级地震的“月－地”关系背景年，以及在“月－地”关系北景年对应的太阳黑子活动周期位相的特定条件下，存在因受特大黑子活动事件，引起太阳磁场极性变化的半周期和全周期为时间尺度的“日－月－地”高相关年的转折变异，激发本区破坏性地震或震群发生的时间规律，并用于对本区未来M≥5级地震活动的中期，短期预报。