Anomalous Heating of the Solar Atmosphere in the Epoch of the Solar Activity Minimum

It is well-known that solar activity is basically caused by the Interaction of magnetic fields with convection and solar rotation, resulting in a great variety of dynamic phenomena, like flares, surges, sunspots, prominences, etc. Many conferences have been devoted to solar activity, including the role of magnetic fields. Similar attention has not been paid to the role of magnetic fields for the overall dynamics and energy balance of the solar atmosphere, related to the general problem of chromospheric and coronal heating. To penetrate this problem we have to focus our attention more on the physical conditions in the ‘quiet’ regions than on the conspicuous phenomena in active regions.

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THE FEATURES OF THE SOLAR ACTIVE REGIONS DISTRIBUTION DURING THE CURRENT SOLAR ACTIVITY MINIMUM

Proceedings of the 24th All-Russia Conference on Solar and Solar-Terrestrial Physics ◽

10.31725/0552-5829-2020-169-172 ◽

2020 ◽

Author(s):

I.G. Kostyuchenko ◽

Keyword(s):

Solar Activity ◽

Active Regions ◽

Solar Activity Minimum ◽

Solar Active Regions

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Nitrate abundance in polar ice during the great solar activity minimum

Advances in Space Research ◽

10.1016/s0273-1177(02)00114-x ◽

2002 ◽

Vol 29 (11) ◽

pp. 1707-1711 ◽

Cited By ~ 4

Author(s):

O.G. Gladysheva ◽

G.E. Kocharov ◽

G.A. Kovaltsov ◽

I.G. Usoskin

Keyword(s):

Solar Activity ◽

Polar Ice ◽

Solar Activity Minimum

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Numerical Short-Term Solar Activity Forecasting

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318000534 ◽

2017 ◽

Vol 13 (S335) ◽

pp. 243-249 ◽

Cited By ~ 2

Author(s):

Huaning Wang ◽

Yihua Yan ◽

Han He ◽

Xin Huang ◽

Xinghua Dai ◽

...

Keyword(s):

Solar Activity ◽

Magnetic Fields ◽

Solar Atmosphere ◽

Magnetic Energy ◽

Three Dimensional ◽

Active Regions ◽

Short Term ◽

Solar Active Regions ◽

Solar Eruptions ◽

Dimensional Reconstruction

AbstractIt is well known that the energy for solar eruptions comes from magnetic fields in solar active regions. Magnetic energy storage and dissipation are regarded as important physical processes in the solar corona. With incomplete theoretical modeling for eruptions in the solar atmosphere, activity forecasting is mainly supported with statistical models. Solar observations with high temporal and spatial resolution continuously from space well describe the evolution of activities in the solar atmosphere, and combined with three dimensional reconstruction of solar magnetic fields, makes numerical short-term (within hours to days) solar activity forecasting possible. In the current report, we propose the erupting frequency and main attack direction of solar eruptions as new forecasts and present the prospects for numerical short-term solar activity forecasting based on the magnetic topological framework in solar active regions.

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The Observed Relationships Between Some Solar Rotation Parameters and the Activity Cycle

Symposium - International Astronomical Union ◽

10.1017/s0074180900029776 ◽

1983 ◽

Vol 102 ◽

pp. 99-111

Author(s):

Robert Howard ◽

Barry J. LaBonte

Keyword(s):

Solar Activity ◽

Solar Rotation ◽

Rotational Velocity ◽

Torsional Oscillation ◽

Periodic Oscillation ◽

Activity Cycle ◽

Solar Activity Cycle ◽

Solar Activity Minimum ◽

Activity Maximum ◽

Open Question

Several parameters of the solar rotation show variations which appear to relate to the phase of the solar activity cycle. The latitude gradient of the differential rotation, as seen in the coefficients of the sin2 and sin4 terms in the latitude expansion, shows marked variations with the cycle. One of these variations may be described as a one-cycle-per-hemisphere torsional oscillation with a period of 11 years, where the high latitudes rotate faster at solar activity maximum and slower at minimum, and the low latitudes rotate faster at solar activity minimum and slower at maximum. Another variation is a periodic oscillation of the fractional difference in the low-latitude rotation between north and south hemispheres. The possibility of a variation in the absolute rotational velocity of the sun in phase with the solar cycle remains an open question. The two-cycle-per-hemisphere torsional waves in the solar rotation also represent an aspect of the rotation which varies with the cycle. We show that the amplitude of the fast flowing zone rises a year before the rise to activity maximum. The fast zone seems to be physically the more significant of the two zones.

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