It is generally believed that sunspots are the emergent part of magnetic flux tubes in the solar interior. These tubes are created at the base of the convection zone and rise to the surface due to their magnetic buoyancy. The motion of plasma in the convection zone being highly turbulent, the surface manifestation of sunspots may retain the signature of this turbulence, including its intermitte...

An automated neural network-based system for predicting solar flares from their associated sunspots and simulated solar cycle is introduced. A sunspot is the cooler region of the Sun's photosphere which, thus, appears dark on the Sun's disc, and a solar flare is sudden, short lived, burst of energy on the Sun's surface, lasting from minutes to hours. The system explores the publicly available s...

In a statistical study of the decay of individual sunspots based on DPR data we find that the mean instantaneous area decay rate is related to the spot radius r and the maximal radius r0 as D = CD r/r0, CD = 32.0±0.26MSH/day. This implies that sunspots on the mean follow a parabolic decay law; the traditional linear decay law is excluded by the data. The validity of the Gnevyshev–Waldmeier rela...

Avian timing of reproduction is strongly affected by ambient temperature. Here we show that there is an additional effect of sunspots on laying date, from five long-term population studies of great and blue tits (Parus major and Cyanistes caeruleus), demonstrating for the first time that solar activity not only has an effect on population numbers but that it also affects the timing of animal be...

In the solar photosphere the magnetic field of magnetic elements and sunspots is known to expand with height. In the case of sunspots this expansion is known to be very rapid, with the field forming an almost horizontal canopy. In this contribution we present new results on the superpenumbral canopy of sunspots based on fits to Stokes I and V profiles of infrared spectral lines. The new models ...

R ecently there has been a renewed discussion in the literature about the determinants of bank runs. Two alternative theoretical explanations are usually provided. According to the first theory, bank runs are exclusively driven by changes in economic fundamentals, such as a deterioration in the return on investment. The second theory views bank runs as a consequence of the existence of multiple...

Sunspots are the subject of interest to many astronomers and solar physicists. Sunspot observation, analysis and classification form an important part of furthering the knowledge about the Sun. Sunspot classification is a manual and thus very labor intensive process that could be automated if it can be successfully learned by a machine. This paper deals with data mining approaches to the proble...

The present study is focused on European beech (Fagus sylvatica L.) growth in eastern Bohemia the Broumovské stěny National Nature Reserve, Czech Republic. objective of this research was to develop an evaluation radial relation solar activity (number sunspots), air temperature growing season, annual precipitation and pollution (SO2 depositions). highest positive significant correlation coeffici...

Aims. We study the visibility of sunspots and its influence on observed values of sunspot region parameters. Methods. We use Virtual Observatory tools provided by AstroGrid to analyse a sample of 6862 sunspot regions. By studying the distributions of locations where sunspots were first and last observed on the solar disk, we derive the visibility function of sunspots, the rate of magnetic flux ...

Sunspots are central to our understanding of solar (and stellar) magnetism in many respects. On the large scale, they link the magnetic field observable in the photosphere to the dynamo processes operating in the solar interior. Properly interpreting the constraints that sunspots impose on the dynamo process requires a detailed understanding of the processes involved in their formation, dynamic...