Solar Activity Growth Research Articles

SARS-CoV-2 virus spreading in depending of the Earth’s magnetic field

The paper presents the results of a study on the possible relationship between the spread of SARS-CoV-2 virus and the Earth’s magnetic field based on an analysis of digital data for 95 countries. Article is based on the statistic data of geomagnetic field and coronavirus disease parameters, which allows, in our opinion, to obtain reliable results of their interpretation, which are as follows:
 The dependence of the spatial expansion of the SARS-CoV-2 virus on the value of modular values of the induction of the Earth’s main magnetic field BIGRF is established. The maximum number of diseases occurs in countries located in regions with reduced (25.0—30.0 mkT) and increased (48.0—55.0 nT) values.
 The SARS-CoV-2 virus expansion of the dynamics of the geomagnetic field over the past 70 years dependence is established. Maximum diseases number refers to areas with maximum changes, in the direction of decrease (up to –6500 nT) and increase 2500 nT).
 Comparison of SARS-CoV-2 disease expansion dynamics with Кр-geomagnetic field perturbation index — shows the practical absence of such connection. The ratio of the maximum daily growth of diseases to the minimums of external geomagnetic activity detected. This ratio may be due to the intensity of galactic cosmic radiation increase during this period.
 The connection between the SARS-CoV-2 disease process dynamics and solar activity is shown, namely: the beginning of a pandemic is due to the superposition of minima of 11 (between 24 and 25) and 110 (120?) solar activity annual cycles. The increase of diseases number correlates well with the increase of the 25th cycle solar activity. The Spanish pandemic was characterized by a similar ratio, which arose about 110 years ago between 14—15 cycles and took place during the 15th cycle of solar activity growth phase.

Evolutionary Changes in the Configuration of the Magnetic Field of the Solar Corona in the Epoch of the Minimum

The evolution of the magnetic configuration in the solar corona is studied. The curvature of the K-corona helmets obtained from an analytical approximation of the geometry of the helmet axis was used as an indicator of the configuration change. The period of minimum solar activity was analyzed with solar eclipse materials. As a result of the analysis, the dependence of the curvature value on the latitude of the position of the helmet base and the phase of the solar cycle has been obtained. It has been established that this dependence is different for the period of solar-activity growth (the beginning of the cycle) and its decline. It was found that there is a sharp decrease in the curvature to almost zero at the beginning of the solar cycle. During the decline of the 23rd cycle and at the beginning of the 24th cycle, the change of the curvature of the helmets differs from the trend of the previous solar cycles. The apparent reason for this is a change in the conditions of the generation of the solar magnetic field. The found latitudinal–phase dependences of the curvature of the coronal helmets indicate a difference in the coronal magnetic configuration during periods of decline and increase in solar activity, as well as a sharp reorganization of the configuration at the beginning of the new solar cycle.

Productivity of dairy cows and quality of milk-raw material with different cosmophysic activity

The results of studies on the relationship between cosmophysical activity and animal productivity (the rhythm of milk yield of cows and the chemical composition of milk, the biochemical composition of raw milk) are presented. It was found that during the phase of growth of the activity of the Sun and the increase in the values of the Wolf index (sunspot) in the first half of the 24-year eleven-year cycle of solar activity, the average value of Wolf (sunspot) numbers varied from 0 to 100. For 2-3 years, at the lower peak of solar activity, and 2-3 years - at the top peak of activity, minimal and unreliable correlation relationships were observed. The most stable connections occur in the middle of an upswing or a decrease in solar activity. An increase in the relationship between the studied indicators was observed when the animals achieved maximum productivity. With an increase in milk yield from 7500 kg to 8500 kg, and further to 10,000 kg, the correlation coefficient was + 0.37, + 0.52 and + 0.64, respectively. The maximum influence of solar activity Wolf (sunspot) numbers) on the average productivity of one animal in the household is manifested at the peak of solar activity growth. It has been established that during the years of the rise of solar activity with low absolute values of Wolf (sunspot) numbers, low yields are more likely, and in high solar activity years, higher dairy values (record) are more likely. It was noted that all the components of milk decreased on days of increasing solar activity. The correlation coefficients for protein and milk fat content with Wolf (sunspot) numbers were r = -0.34 and r = -0.22, P 0.95. Correlation analysis revealed a reliable correlation of bacterial contamination and the number of somatic cells r = +0.28 and r = +0.31 (at P 0.95), respectively, with the Wolf (sunspot) numbers. In the collection milk, the negative correlation by fat content r = -0.12, density r = -0.18, acidity r = -0.17, protein content r = -0.19, sugar content r = -0.14, minerals r = -0.17 was observed with an increase in solar activity.

Cosmic ray modulation during the solar activity growth phase of cycle 24

Recent years allowed us to study long-term variations in the cosmic ray (CR) intensity at an unusually deep solar activity (SA) minimum between cycles 23 and 24 and during the SA growth phase in cycle 24, which was the cycle when SA was the lowest for the epoch of regular ground-based CR observations since 1951. The intensity maximum, the value of which depends on the particle energy, was observed in CR variations during the period of an unusually prolonged SA minimum: the CR density during the aformentioned period (2009) is higher than this density at previous CR maxima in cycles 19–23 for low-energy particles (observed on spacecraft and in the stratosphere) and medium-energy particles (observed with neutron monitors). After 2009 CR modulation at the SA growth phase was much weaker over three years (2010–2012) than during the corresponding SA growth periods in the previous cycles. The possible causes of this anomaly in CR variations, which are related to the CR residual modulation value at a minimum between cycles 23 and 24 and to variations in SA characteristics during this period, were examined. The contribution of different solar magnetic field characteristics and indices, taking into account sporadic solar activity, has been estimated.

Stability of the seasonal variations in diurnal and semidiurnal components of mid-latitude F2 layer parameters

We report work utilizing 15-min resolution ionospheric data obtained with DPS-4 digisonde in 2003–2011 to study the seasonal variations in amplitudes and phases of the most powerful spectral components of the F2 layer critical frequency (foF2) and peak height (hmF2) fluctuations over Irkutsk (52.5°N, 104.0°E). We show that fluctuations of both parameters contain quasi-harmonic components with periods of Tn=24/nh (n=1–7). The number of distinct spectral peaks varies from 3 in summer to 7 in winter. Amplitude and phase characteristics of the diurnal (n=1) and semidiurnal (n=2) components is studied using the data sets extracted from the original data sets with band-pass filter. It has been found that the amplitudes of diurnal/semidiurnal foF2 and diurnal hmF2 components are maximum in winter and minimum in summer. Amplitudes of the diurnal components vary gradually; those of the foF2 semidiurnal one, abruptly, thus forming a narrow winter maximum in November–January. The phase (local time of maximum) of the diurnal foF2 component increases gradually by 4–6h from winter to summer. The phase of the semidiurnal foF2 component is nearly stable in winter/summer and sharply decreases (increases) by 2–3h near the spring (autumn) equinox. The phase of the diurnal component of hmF2 (local time of minimum) varies slightly between 1130 and 1300 LT; that of the semidiurnal one decreases (increases) by 4–6h from January to March (from September to November). The results obtained show that the main features of seasonal variations in the diurnal and semidiurnal components of the mid-latitude F2 layer parameters recur consistently during the solar activity growth and decline phases.

Ionospheric response to solar flares of C and M classes in January–February 2010

The ionospheric response to solar flares is analyzed for the case of the beginning of solar activity growth, when the background ionization of the ionosphere is still low enough. It is shown that the algorithms and methods of averaging variations and derivative of the total electron content (TEC) over the entire sunlit ionosphere almost always make it possible to identify the ionospheric response even to close in time weak solar flares of the C class. It is found that the response to a solar flare rather intense in the X-ray range can have almost no manifestations, which is caused by the fact that the flare does not reveal itself in the ultraviolet part of the spectrum. A map of the TEC derivative over the Japan territory with an average resolution of ∼18 km is drawn for the M6.4 flare (February 7, 2010). Before the flare maximum, the TEC derivatives are synchronously increasing over the entire Japan, while after the flare maximum the values of the TEC derivative vary not so synchronously, and local differences are seen.

VHF radio response of the near Earth space during solar activity growth in October, 2003

The analysis of observations of very high frequency radio noise intensity at the middle latitude on a frequency f=500MHz from 14th till 26th of October, 2003 is presented. These data are compared with the solar radio bursts in the range of frequencies 1–14MHz registered by RAD2 receiver of the WAVES device installed on board the WIND spacecraft.The sporadic enhancement of near Earth very high frequency radio noise were observed with the help of ground radio telescope preferably either in pre mid night hours or at daytime. In many cases between October 17 and 22 short-term increases of the fluxes of low energy electrons, protons and ions in the interplanetary space by hundreds of times, corresponded to VHF radio bursts. At the same time slow increasing of solar cosmic rays streams at Lagrange point L1 and on geostationary orbit during October, 21 and 22, did not affect the usual radio noise level. A strong solar flare of 1B/X5.5 class on October 23 contributed to a prolonged rise of the intensity level of spectral radio emission, including the night sector of magnetosphere. It is assumed that very high frequency radio bursts in the near Earth space may appear when the processes of penetration of interplanetary low energy charge particles into Earth plasmasphere take place.

Optical observations of large-scale undulations in the 23rd cycle of solar activity

A statistical analysis of observations of large-scale undulations during the 23rd cycle of solar activity was performed using optical data from two stations: Tixie (71.6°N, 128.9°E) and Zhigansk (66.8°N, 123.4°E). The total number of events recorded was 54 (43 events at Tixie and 11 at Zhigansk). The complete list of observed events is presented. The occurrence frequency of eveningside (17–23 LT) undulations during the solar activity growth (1999) and decline (2003–2005) phases tends to increase. Large-scale undulations were shown to be generated both on the equatorward boundary of the diffuse auroral zone and inside the diffuse zone, which does not necessarily occur during magnetic storms.

Analysis of large-scale horizontal velocities and the magnetic field on the sun during fast reorganization periods

The velocity field of large-scale magnetic structures during fast reorganizations of the global solar magnetic field structure has been analyzed. Some characteristic features of the velocity field have been found during these periods. At that time, a considerable part of the solar surface is occupied by regions with low horizontal velocities, which correspond to the regions of positive and negative velocity field divergence during the solar activity growth and decline phases, respectively. Such character of changes in the velocity field during these periods agrees with the previously proposed scenario of magnetic field variations during global reorganizations of the magnetic field structure. The average horizontal velocities during a Carrington rotation and their divergence have been calculated for Carrington rotations from 1646 to 2006. Relatively slow regular variations in these parameters as well as their abrupt changes, observed during different solar cycle phases, have been revealed. An increase in the average horizontal velocity during the solar activity growth phase is most probably caused by relative motions of the regions with a new emerging magnetic flux. We assume that abrupt increases in the average horizontal velocity divergence are related to fast reorganizations of the magnetic field structure.

Conditions of formation of transpolar coronal holes

[1] The longitudinal distribution of high-latitude coronal holes is considered. To accomplish the task, polar projections of synoptic charts of He 10830 ˚ observations of the Kitt Peak observatory for the period 1975‐2003 were made, and coronal holes were identified as regions of increased emission. A number of structures could be interpreted as coronal holes beginning at middle or low latitudes, reaching the pole, and descending again to the equator along meridians in another longitudinal interval. Thus such coronal holes are extended along a meridional line crossing the pole, and their lifetime is several rotations. Such structures are most distinct 1‐2 years after the end of the polarity reversal of the solar magnetic field in the phase of solar activity decrease and, in some cases, in the phase of the solar activity growth. As a rule, at the opposite solar pole, there exist coronal holes extended along meridional lines in other longitudinal sectors. Comparison with distribution of magnetic fields for this period has been performed. The possibility that such coronal holes can aect recurrent disturbances of geomagnetic indexes is considered. INDEX TERMS: 7511 Solar Physics, Astrophysics, and Astronomy: Coronal holes; 7524 Solar Physics, Astrophysics, and Astronomy: Magnetic fields; 7536 Solar Physics, Astrophysics, and Astronomy: Solar activity cycle; KEYWORDS: High-latitude coronal holes; Longitudinal distribution; Solar magnetic field.

Near-mesopause temperatures registered over Yakutia

The results of night-time near-mesopause temperature measurements carried out with an infrared spectrograph at the Maimaga station (63° N, 129.5° E) near Yakutsk are presented. The kinetic temperature of the mesosphere region around 87 km was determined from the intensity distribution of the rotational lines of a hydroxyl molecular band. Mean temperatures obtained during 217 nights, from August 1997 to April 2000, were used to study seasonal variations of the upper mesosphere temperature and the relationship of temperature changes with solar activity. Analysis of the monthly averaged atmospheric temperature at the height of the nightglow hydroxyl emissions (∼87 km) at various latitudes (Urbana (40° N, 88° W) , Haute-Provence (44° N, 6° E) , Stockholm (59.5° N, 18.2° E) , Yakutsk, and Andenes (69° N, 16° E) ) has shown that seasonal oscillations at Yakutsk closely correspond to high latitude conditions despite the great difference in longitude. At mid-latitudes the mesosphere is warmer in winter while at high latitudes warmer temperature is observed in spring and in autumn. The measurements from Yakutsk suggest that the temperature at the height of the hydroxyl emission increases with solar activity growth.