Superconcentration of photospheric sources of the large-scale open solar magnetic field in the main zone of active longitudes, differential rotation blocking, and origination of the four-sector structure. 1. The field and solar activity dynamics

The phenomena of superconcentration of the large-scale field photospheric sources in the main zone of active longitudes, blocking of regular differential rotation by these sources, and origination of the four-sector structure of the solar magnetic field during the decline phase of cycle 23 have been considered in more detail and taking into account the polar correction. It has been indicated that superconcentration was formed due to the penetration of photospheric sources into the zone from the western surroundings of this zone and owing to the generation of the large-scale field in the zone itself. The dynamics of a blocking-induced complex MHD disturbance with reflected from the zone and reconnecting photospheric sources of negative and positive polarity, respectively, and the transformation of the bisector structure into the four-sector one have been considered. It has been indicated that the dynamics of this MHD disturbance was responsible for that of associated solar activity: the generation of sunspot groups, appearance of flares, and, finally, origination of a powerful heliospheric storm and the solar-terrestrial extrastorm of July 22–27, 2004.     

MHD nature of the origination,dynamics, geoeffectiveness,and disappearance of the four-sector structure of the solar magnetic field during the cycle 23 decline phase

The MHD nature of the origination, dynamics, geoeffectiveness, and disappearance of the four-sector structure of the solar magnetic field during the cycle 23 decline phase has been established. A prolonged ordered MHD process including the chain of the interrelated phenomena (unknown before this study), which begin and end in one of the main zones of active longitudes and are responsible for the above nature of the four-sector structure, has been detected as a result of the simulation of the large-scale open solar magnetic field and an analysis of the dynamics of this field fluxes. These phenomena are as follows: the extreme concentration of the photospheric field sources of the same sign in the zone of active longitudes; blocking of regular differential rotation by these sources; origination of a nonstationary MHD disturbance in the form of a four-sector structure, traveling in the direction of solar rotation at a nearly Alfvén velocity; upset of blocking, displacement of blocking sources from the zone, and their shearing motion relative to a traveling MHD disturbance; deceleration and dissipation of a four-sector MHD disturbance; and reconstruction of a bisector structure. The interactions during this process, which lasted from May 2004 to December 2005, were accompanied by the generation of an ordered succession of heliospheric and solar-terrestrial disturbances including the series of nine extrastorms that were observed from July 2004 to September 2005 and were the last storms in the finished cycle 23 of solar activity.     

Intersector disbalance of the large-scale open solar magnetic field fluxes,active and passive boundaries,and solar-terrestrial extrastorms

The dynamics (from rotation to rotation) of the absolute values of the large-scale open solar magnetic field fluxes in the four-sector field structure has been considered for the first time, using CRs 2032–2035 in July–October 2005 as examples. An important role of the ratio of the fluxes at the eastern and western sector boundaries (Φ _E /Φ _W ) is confirmed. As in the cases of the two-sector structure, Φ _E /Φ _W > 1 is typical of active rigidly corotating boundaries with intense sunspot formation, flares, and interplanetary and geomagnetic disturbances. A remarkable property of the considered structure was the presence of a rapidly increasing flux in an initially narrow sector and the flux interaction with a stable rigidly corotating sector in the zone of the main active longitudes, which caused an unexpectedly strong geoeffective long-range action of flares near the corresponding active boundary.     

Beginning of the new solar cycle (cycle 24) in the large-scale open solar magnetic field

It is proposed to determined minimums of the 11-year solar cycles based on a minimal flux of the large-scale open solar magnetic field. The minimal fluxes before the finished cycle 23 (Carrington rotation CR 1904) and the started cycle 24 (CR 2054, April 2007) were equal to 1.8 × 10²² and 1.2 × 10²² μs, respectively. The long-term tendency toward an approach to a deep minimum of solar activity is confirmed. On the assumption that magnetic flux variations from minimums to maximums are proportional to each other, the anticipated value of the maximal Wolf number during cycle 24 is estimated as W _max = 80.     

地球主磁场电磁转矩导致的地球差异旋转

为探索驱动地球系统差异旋转的力源,选择整个地球作为研究对象,应用经典电磁学理论,分析地球固体介质中的电荷在地球主磁场中的运动特点,发现存在一个与地球自转方向相反的切向洛伦兹力.通过电荷与介质间的相互作用,切向洛伦兹力传递至介质迫使介质西漂.为探索地球差异旋转的规律,建立了地球薄圆筒圈层模型.应用经典物理学理论和方法推导出了地球主磁场电磁转矩及其产生的角加速度公式.研究得到四点主要结论:1)作用于半径不同的地球薄圆筒圈层的地球主磁场电磁转矩及其产生的角加速度绝对值不同:地轴及赤道附近圈层的小,其自转相对较快;半径等于3～(1/2)倍地球半径的薄圆筒圈层及其相邻圈层的大,其自转相对较慢.2)同一薄圆筒圈层中的差异旋转缘于介质的介电常数、阻力系数及质量密度的差异.3)地球差异旋转缘于地球的自转、正负电荷的非对等分布及介质的介电常数、阻力系数、质量密度的差异.4)地球差异旋转导致地壳运动,孕育地震,地球主磁场是地球差异旋转和地震孕育的敏感因子.     

Role of the solar main magnetic dipole field in the solar-tropospheric relations. Part II. Dependence on the types of solar sources

Two criteria have previously been reported for efficient solar-tropospheric relations through corpuscular channels: the appropriate Sun-Earth attitude (equinoxes) and the mutual orientations of the terrestrial and solar main magnetic dipole fields. The effect also depends on the geographical position. The present paper reports a further criterion. The solar-meteorological correlations also depend on the solar origin of the given corpuscular impact: disturbances originating from the polar and equatorial regions release opposite behaviours. We conclude that the solar-meteorological relations can only be described by taking into account the specific spatial situations and polarity distributions.     

Role of the solar main magnetic dipole field in the solar-tropospheric relations. Part I. Semiannual fluctuations in Europe

The influence of the solar corpuscular radiation on weather is demonstrated by characterizing the corpuscular impact by means of the geomagnetic aa-index and the terrestrial response by European temperature data. Considering different spatial and vectorial circumstances the following conclusions can be drawn: 1. the efficiency of the corpuscular impact depends on the Sun-Earth attitude (semiannual fluctuation); 2. this regularity depends on the polarity of the solar main magnetic dipole field; and 3. the whole complex of phenomena also depends on the geographic position - it exists at European middle latitudes but it does not exist in northern and southern Europe. We conclude that the periods of differently or oppositely working mechanisms should be separated in order to recognize the regularities.     

Auroral electrojet dynamics during magnetic storms, connection with plasma precipitation and large-scale structure of the magnetospheric magnetic field

Effect of the equatorward shift of the eastward and westward electrojets during magnetic storms main phase is analyzed based on the meridional chains of magnetic observatories EISCAT and IMAGE and several Russian observatories (geomagnetic longitude ≈110°, corrected geomagnetic latitudes 74°>φ>51°.) Magnetic storms of various Dst index intensity where the main phase falls on 1000 UT - 2400 UT interval were selected so that one of the observatory chains was located in the afternoon - near midnight sector of MLT. The eastward electrojet center shifts equatorward with Dst intensity increase: when Dst ≈ −50 nT the electrojet center is located at φ ≈ 62°, when Dst ≈ −300 nT it is placed at φ ≈ 54°. The westward electrojet center during magnetic storms main phase for intervals between substorms shifts equatorward with Dst increase: at φ ≈ 62° when Dst ≈ −100 nT and at φ ≈ 55° when Dst ≈ −300 nT. During substorms within the magnetic storms intervals the westward electrojet widens poleward covering latitudes φ ≈ 64°–65°. DMSP (F08, F10 and F11) satellite observations of auroral energy plasma precipitations at upper atmosphere altitudes were used to determine precipitation region structure and location of boundaries of various plasma domains during magnetic storms on May 10–11, 1992, February 5–7 and February 21–22, 1994. Interrelationships between center location, poleward and equatorward boundaries of electrojets and characteristic plasma regions are discussed. The electrojet center, poleward and equatorward boundaries along the magnetic observatories meridional chain were mapped to the magnetosphere using the geomagnetic field paraboloid model. The location of auroral energy oxygen ion regions in the night and evening magnetosphere is determined. Considerations are presented on the mechanism causing the appearance in the inner magnetosphere during active intervals of magnetic storms of ions with energy of tens KeV. In the framework of the magnetospheric magnetic field paraboloid model the influence of the ring current and magnetospheric tail plasma sheet currents on large-scale magnetosphere structure is considered.     

Correlation between the parameters of coronal mass ejections and features of their propagation in the corona with the large-scale structure of the solar magnetic field

Correlation between the parameters of coronal mass ejections (CMEs) that are detected on the LASCO coronographs and are associated with eruptive prominences and the distances of CME axes from the coronal streamer belt has been analyzed. The deviations of CME trajectories from the radial direction have been investigated.     

Relationship between cyclic variations in the velocity and occurrence frequency of coronal mass ejections and cyclic changes in the structure of the large-scale solar magnetic field

This paper investigates the relationship between cyclic variations in the velocity of coronal mass ejections and cyclic changes in the structure of the large-scale solar magnetic field (LSSMF) in solar cycle 23, using the effective solar multipole index as a parameter of the characteristic dimensions of LSSMF structural elements. Cyclic variations in the velocity and frequency of coronal mass ejections are found to resemble cyclic changes in the effective solar multipole index. It is suggested that cyclic changes in the maximum velocity of coronal mass ejections are associated with different conditions for the formation of complexes of active regions connected by coronal arch structures, the energy of which is the main source of energy (velocity) for coronal mass ejections. The study leads to some suggestions about the possible site of initiation of coronal mass ejections.     

The dynamics of solar activity and anomalous weather of summer 2010: 2. Relationship with the active longitude zone; effects in the west and east

We confirm the close synoptic relationship of the sectoral structure of the Sun’s magnetic field of the with the near-Earth tropospheric pressure with a case study of three European points (Troitsk, Rome, Jungfrau) in the period of the anomalously hot summer of June–August 2010. We substantiate the position that such a relationship was fostered by the anomalously low solar activity as a result of superposition of the minima of the 22- and 180-year cycles. Sectoral analysis of the solar-tropospheric relationships has shown that the appearance of a blocking anticyclone in the Moscow suburbs, its expansion to Rome and Jungfrau, and subsequent retreat at first from these points, and then from the Moscow suburbs was closely related to solar activity phenomena producing, according to contemporary notions, cyclonic activity, shown by simulation of the Earth’s electric field.     

The 11-year solar cycle, the Sun's rotation, and the middle stratosphere in winter. Part II: Response of planetary waves

The effect of the 11-year solar cycle on the response of planetary wavenumbers 1 and 2 at 10 and 30 hPa in winter to solar activity oscillations on the time scale of the Sun's rotation (27.2 day) is discussed in terms of statistical spectral analysis. The three oscillations studied are the 27.2 d (period of the Sun's rotation), 25.3 d (periodicity caused by modulation of the 27.2 d stratospheric response by annual atmospheric variation), and 54.4 d (doubled period of the solar rotation). A significant effect of the 11-year solar cycle is found for the 54.4 d periodicity in planetary wavenumber 1, and for the 27.2 and 25.3 d periodicities in planetary wavenumber 2. The effect of the 11-year solar cycle is expressed in the evident differences between the amplitudes of responses of planetary waves at maximum and minimum of the solar cycle: the amplitudes are much larger at high than at low solar activity. The 11-year modulation of planetary wave activity is most pronounced at mid-latitudes, mainly at 40–60°N, where the observed variability of planetary waves is large. The results obtained are in good agreement with results of the recent modeling study by Shindell et al. (Science 284 (1999) 305).     

Dependence of geomagnetic activity during magnetic storms on the solar wind parameters for different types of streams: 2. Main phase of storm

The paper analyses the development of the main phase of magnetic storms with Dst ≤ −50 nT, the interplanetary source of which consists of eight types of solar wind streams: magnetic clouds (MC, 17 storms); corotating interaction regions (CIR, 49 storms); Ejecta (50 storms); compressed region (Sheath) before Ejecta Sh_E (34 storms); the Sheath before a magnetic cloud Sh_MC (6 storms); all Sheath before all ICME, Sh_E + Sh_MC (40 storms); all ICME, MC + Ejecta (67 storms); and an indeterminate type of stream IND (34 storms).     

2-D P-wave velocity structure of lithosphere in the North China tectonic zone: Constraints from the Yancheng-Baotou deep seismic profile

We obtained the 2-D P-wave velocity structure of the lithosphere in the eastern North China Craton, Shanxi fault subsidence zone, and Yinchuan-Hetao fault subsidence zone by ray tracking technology based on six groups of clearly identified crustal phases and one group of lithospheric interface reflection phases from seismic recording sections of 21 shots along the 1300-km-long Yancheng-Baotou deep seismic wide-angle reflection/refraction profile. The results indicate significant differences between the lithospheric structure east and west of the Taihang Mountains, which is a gravity-gradient zone as well as a zone of abrupt change in lithospheric thickness and a separation zone of different rock components. East of the Taihang Mountains, the Mesozoic and Cenozoic lithospheric structure of the North China Craton has undergone strong reformation and destruction, resulting in the lithosphere thickness decreasing to 70–80 km. The North China Basin has a very thick Cenozoic sedimentary cover and the deepest point of crystalline basement is about 7.0 km, with the crustal thickness decreasing to about 31.0 km. The crystalline basement of the Luxi uplift zone is relatively shallow with a depth of 1.0–2.0 km and crustal thickness of 33.0–35.0 km. The Subei Basin has a thicker Cenozoic sedimentary cover and the bottom of its crystalline basement is at about 5.0–6.0 km with a crustal thickness of 31.0–32.0 km. The Tanlu fault is a deep fracture which cuts the lithosphere with a significant velocity structure difference on either side of the fault. The Tanlu fault plays an important role in the lithospheric destruction in the eastern part of the North China Craton. West of the Taihang Mountains, the crustal thickness increases significantly. The crust thickness beneath the Shanxi fault depression zone is about 46 km, and there is a low-velocity structure with a velocity of less than 6.1 km s?? in the upper part of the middle crust. Combined with other geophysical study results, our data shows that the lithospheric destruction at the Shaanxi-Shanxi fault depression zone and the Yinchuan-Hetao rift surrounding the Ordos block is non-uniform. The lithosphere thickness is about 80–90 km in the Datong-Baotou area, 75–137 km at the Dingxiang-Shenmu region, and about 80–120 km in the Anyang-Yichuan area. The non-uniform lithospheric destruction may be related to the ancient tectonic zone surrounding the Ordos block. This zone experienced multi-period tectonic events in the long-term process of its tectonic evolution and was repeatedly transformed and weakened. The weakening level is related to the interactions with the Ordos block. The continental collision between the Cenozoic India and Eurasia plates and N-E thrusting by the Qinghai Tibet Plateau block is causing further reformation and reduction of the lithosphere.     

Cosmic ray flux variations,modulated by the solar and terrestrial magnetic fields,and climate changes. Part 2: The time interval from ∼10000 to ∼100000 years ago

A joint analysis of paleodata on variations in cosmic ray fluxes, solar activity, geomagnetic field, and climate during the period from ～10000 to ～100000 years ago has been performed. Data on the time variations in the concentration of ¹⁴C and ¹⁰Be cosmogenic isotopes, which are generated in the Earth’s atmosphere under the action of cosmic ray fluxes modulated by solar activity and geomagnetic field variations, were used to detect variations in solar activity and the geomagnetic dipole. Information about climate changes has been obtained mainly from variations in the concentration of stable isotopes in the natural archives. A performed analysis indicates that the variations in cosmic ray fluxes under the action of variations in the geomagnetic field and solar activity are apparently one of the most effective natural factors of long-term climate changeability on a large time scale.     

Variations in the cosmic ray fluxes,modulated by the solar and terrestrial magnetic fields,and climate changes. Part 3: A time interval of 1.5 Myr,including the pleistocene

The most reliable data on a change in the intensity of cosmic rays and geomagnetic field on large time scales have been analyzed, and the relations between changes in these processes and climate during the last 1.5 Myr have been studied. An analysis indicated that the climate of the Earth is affected by changes in the Earth’s orbit parameters and geomagnetic dipole values; however, the climate responds to these changes with a delay of 10 kyr and immediately, respectively. In this case about two thirds of the effect of eccentricity on ¹⁸O is implemented via an intermediate chain: virtual axial dipole moment, changes in which can be related to changes in eccentricity. Thus, an analysis of the accumulated data on the processes, proceeding in the Earth’s atmosphere during the interaction with cosmic rays on the scales of several years to several hundreds of thousand years, indicates that the cosmophysical factor of influence on climate cannot be rejected. To make the conclusion more convincing, it is necessary to collect data for the studied time interval in a much wider region, to more accurately date samples, and to study the response of the climatic system to the external influence.     

Comments on: The structure of the shallow crust beneath Olkaria geothermal field, Kenya, deduced from gravity studies, by J.M. Ndombi

Major geothermal systems in the Kenya Rift Valley are located over, or near to, elongated axial gravity highs. A recently published interpretative model, which explains the axial gravity high over the Olkaria geothermal field in terms of shallow dyke intrusions, is not acceptable. This conclusion is corroborated by density measurements on surface samples and cores from production bores in the Olkaria field. Elongated, high-standing mafic intrusions are the likely source of the axial gravity highs in the rift valley. These intrusions appear to be the heat source for most geothermal systems in the rift.     

Anomalous polarization features of the cyclotron radiation source in the NOAA 7123 active region: The structure, dynamics, and reasons of occurrence

The research results of the unique NOAA 7123 active region (April 1992) are presented; its anomalous polarization features (long-term predominance of O-mode radiation above the central part of the main sunspot) were previously revealed by VLA observations with a resolution of (2–4)” at wavelengths of 3.6 and 6.4 cm (Vourlidas et al., 1997). Additional observations in a wider band of electromagnetic radiation, including, in particular, spectrum-polarization observations performed with the RATAN-600 and SSRT radio telescopes, are considered. The analysis of these data allowed for the conclusion that the anomaly was caused by the presence of a cold substance in the upper coronal layers, starting from the height where (6–7) cm radiation was generated. A possible transportation agent of this substance—Hα filament—one of the bases of which fell on the sunspot’s umbra-penumbra boundary, was found.     

Jom-Bolok Holocene volcanic field in the East Sayan Mts., Siberia,Russia: structure,style of eruptions,magma compositions,and radiocarbon dating

Jom-Bolok volcanic field is located in the East Sayan Mts. of Siberia (Russia), a portion of the Asian convergent zone. It is located at the boundary of the Riphean Tuva-Mongolia massif, which was probably reactivated because of the interplay between far-field tectonic stress derived from the India–Asia collision zone and extension in the south-western Baikal rift system. The volcanic field comprises a number of hawaiitic lava flows, of various lengths, which flowed down paleorivers. Flows were fed by fissure eruptions and the largest lava flow field was dated as 7,130?±?140 cal ¹⁴C years BP using a buried organic sample found inside the associated cinder cone. This lava flow field is about 70 km long, ～100 km² in area, and 7.9 km³ in volume. The area and volume of this flow field ranks this eruption highly in the global record of fissure-fed effusive eruptions. This lava flow field makes up 97% of the entire Jom-Bolok volcanic field, a fact which raises a puzzling question: why and/or how did a relatively small-volume volcanic field produce such a large-volume individual eruption? A working hypothesis is that a pond of sublithospheric melt accumulated over a relatively prolonged period. This was then rapidly drained in response of tectonic changes triggered by unloading of ice in the Early Holocene.