Records of sunspot and aurora observations in pre-telescopic historical documents can provide useful information about solar activity in the past. This is also true for extreme space weather events, as they may have been recorded as large sunspots observed by the naked eye or as low-latitude auroras. In this paper, we present the results of a comprehensive survey of records of sunspots and auro...

We show that extrinsic or non-fundamental uncertainty influences markets in a controlled environment. This work provides the first direct evidence of sunspot equilibria. These equilibria require a common understanding of the semantics of the sunspot variable, and they appear to be sensitive to the flow of information. Extrinsic uncertainty matters when information flows slowly, as in a call mar...

An understanding of the Ohl's Precursor Method, which is used to predict the upcoming sunspots activity, is presented by employing a simplified movable divided-blocks diagram. Using a new approach, the total number of sunspots in a solar cycle and the maximum averaged monthly sunspots number Rz(max) are both shown to be statistically related to the geomagnetic activity index in the prior solar ...

Recent satellite measurements of the solar total irradiance (S) indicate that on time scales of days to months the solar constant varies by a few tenths of a percent. The predominant part of these variations can be explained by blocking of the upward solar flux by sunspots. The observations are consistent with current theoretical models of energy storage in which the energy blocked by the sunsp...

This article is a continuation of the works1-4 author, devoted to elucidating physical nature dark sunspots. It has been proven that scientific paradigm cold sunspots prevailing in solar physics erroneous, since it contradicts second law thermodynamics. photosphere can only be hotter than photosphere, and their visual darkness non-thermal nature. Sunspots are hottest areas Sun's surface, temper...

Due to their high intensity of emission in the O VI 1031.9 and 1037.6Å lines, even small sunspots on the solar disk can strongly influence the intensity of the radiative scattering component of O VI lines in the corona. Observations of O VI disk spectra show a 1032/1038 line intensity ratio of >2.6 in a sunspot compared to quiet disk values of ∼2. The enhancement of the 1032 line in comparison ...

Abstract The Haihe River basin is the main grain production base and highland of economic strategic development in China. Based on daily meteorological data during 1960–2020, characteristics drought evolution were analyzed by standardized precipitation evapotranspiration index (SPEI). Pearson correlation method cross-wavelet analysis used to explore between SPEI climate factors (global warming,...