Complexes of activity on the Sun in solar cycle 21

The paper provides statistical data on solar activity complexes (ACs) observed in solar cycle 21. From the synoptic charts for the 1976–1986 sunspot activity, we have detected the regions where the sunspot generation was observed at least through three Carrington Rotations (CRs). These regions were identified as AC cores. We have compiled an AC catalogue. ACs are shown to evolve quasi-periodically, in pulses that are 15–20 rotations long. We have analyzed the North-South asymmetry in the AC location. In cycle 21, 90 % of the proton flares that affected the natural environment are shown to have occurred in ACs. We note a tendency for AC activity to decrease, as well as the manifestation of the Gnevyshev—Ohl rule in AC properties, in solar cycles 21–24.

Complexes of activity on the Sun in solar cycle 21

The paper provides statistical data on solar activity complexes (ACs) observed in solar cycle 21. From the synoptic charts for the 1976–1986 sunspot activity, we have detected the regions where the sunspot generation was observed at least through three Carrington Rotations (CRs). These regions were identified as AC cores. We have compiled an AC catalogue. ACs are shown to evolve quasi-periodically, in pulses that are 15–20 rotations long. We have analyzed the North-South asymmetry in the AC location. In cycle 21, 90 % of the proton flares that affected the natural environment are shown to have occurred in ACs. We note a tendency for AC activity to decrease, as well as the manifestation of the Gnevyshev—Ohl rule in AC properties, in solar cycles 21–24.

A Hard-Science Approach to Kondratieff’s Economic Cycle

In an effort to evidence the Kondratieff cycle more scientifically than the way economists do, physical variables are studied rather than monetary indicators. Previously published graphs are reproduced and updated here with recent data. A cyclical rather regular variation of energy consumption reveals a 56-year cycle. A dozen human endeavors/phenomena, such as bank failures, homicides, hurricanes, feminism, and sunspot activity are shown to resonate with this cycle. Possible explanations for this phenomenon may have to do with a climatic variation or with the length of time any individual actively influences the environment. There is some evidence that the cycle may be getting shorter in amplitude and duration in recent years. All quantitative confidence levels involved in these observations are poor by scientific standards and permit critics to question the very existence of this phenomenon.

Spatial-Temporal Characteristics And Influencing Factors of Climatic Growth Period of Chimonophilous Crop In Hexi Oasis During 1960-2019

Based on the daily average temperature data of 6 meteorological stations in the Hexi Oasis, Gansu Province, where the chimonophilous crop distribution area is located from 1960 to 2019. The spatio-temporal characteristics and influencing factors of the starting and ending days of the growth period, the number of days, and the effective accumulated temperature (Abbreviated as EAT) of the growing period of the chimonophilous crop in the Hexi Oasis was analyzed by Using climate tendency rate, ArcGIS inverse distance weighted interpolation, Mann-Kendall test, Morlet wavelet analysis, principal component analysis and correlation analysis methods, etc. The results show that there are significant differences in the spatio-temporal changes in the climate growth period of the chimonophilous crop in the Hexi Oasis. It shows a trend of decreasing from southeast to northwest, except for Yongchang (the highest elevation and lowest temperature in Yongchang). The M-K test showed that the growth period termination date was the most sensitive response to climate warming. Wavelet analysis shows the climatic growth period changes of cool-loving crops in the study area coincide with the cycles of atmospheric circulation 2-4a, El Niño 2-7a and sunspot activity quasi-11a.The changes are affected not only by 74 atmospheric circulation factors, but also by geographic parameters such as latitude and altitude, and monthly average temperature. This study provides scientific decision-making and basis support for the development of food and crop security and the improvement of the ability to withstand disasters in the Hexi Oasis. At the same time, it is of important theoretical significance and practical value for coping with climate change and proposing countermeasures for disaster prevention and mitigation.

Correlation study between sunspot and rainfall in Udaipur subregion

ABSTRACT. The cross correlation among 102 years rainfall data in Udaipur subtropical region and sunspots show tpe influence of solar activity on the climatic conditions of Udaipur. The periodicity obtained using rainfall and other data sets. such as. water storage of Jaisamand lake and gauge measurements of two rivers. Jakham and Karmoi, are similar to the periodicity of sunspots, which indicates a relationship between rainfall and sunspot activity. A period of about 27% is found to deviate from normal rains in the form of flood. excess and deficit of rains in Udaipur sub-tropical region. The possible physical mechanisms to explain sun-weather relationship in astro-physical context are discussed.

The North–South Asymmetry of Sunspot Relative Numbers Based on Complex Network Technique

Solar magnetic activity exhibits a complex nonlinear behavior, but its dynamic process has not been fully understood. As the complex network technique can better capture the dynamics of nonlinear system, the visibility graphs (VG), the horizontal visibility graphs (HVG), and the limited penetrable visibility graphs (LPVG) are applied to implement the mapping of sunspot relative numbers in the northern and southern hemispheres. The results show that these three methods can capture important information of nonlinear dynamics existing in the long-term hemispheric sunspot activity. In the presentation of the results, the network degree sequence of the HVG method changes preferentially to the original data series as well as the VG and the LPVG, while both the VG and the LPVG slightly lag behind the original time series, which provides some new ideas for the nonlinear dynamics of the hemispheric asymmetry in the two hemispheres. Meanwhile, the use of statistical feature-skewness values and complex network visibility graphs can yield some complementary information for mutual verification.

Possible Linkages of Hydrological Variables to Ocean–Atmosphere Signals and Sunspot Activity in the Upstream Yangtze River Basin

Profiling the hydrological response of watershed precipitation and streamflow to large-scale circulation patterns and astronomical factors provides novel information into the scientific management and prediction of regional water resources. Possible contacts of El Niño–Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), sunspot activity to precipitation and streamflow in the upper Yangtze River basin (UYRB) were investigated in this work. Monthly precipitation and streamflow were utilized as well as contemporaneous same-scale teleconnections time series spanning a total of 70 years from 1951 to 2020 in precipitation and 121 years from 1900 to 2020 in streamflow. The principal component analysis (PCA) method was applied so as to characterize the dominant variability patterns over UYRB precipitation time series, with the temporal variability of first two modes explaining more than 80% of total variance. Long-term evolutionary pattern and periodic variation characteristics of precipitation and streamflow are explored by applying continuous wavelet transform (CWT), cross-wavelet transform (XWT) and wavelet coherence (WTC), analyzing multi-scale correlation between hydrological variables and teleconnections in the time-frequency domain. The results manifest that ENSO exhibits multiple interannual period resonance with precipitation and streamflow, while correlations are unstable in time and phase. PDO and sunspot effects on precipitation and streamflow at interannual scales vary with time-frequency domains, yet significant differences are exhibited in their effects at interdecadal scales. PDO exhibits a steady negative correlation with streamflow on interdecadal scales of approximately 10 years, while the effect of sunspot on streamflow exhibits extremely steady positive correlation on longer interdecadal scales of approximately 36 years. Analysis reveals that both PDO and sunspot have significantly stronger effects on streamflow variability than precipitation, which might be associated with the high spatiotemporal variability of precipitation.

Evolution of Storm Surges over the Little Ice Age Indicated by Aeolian Sand Records on the Coast of the Beibu Gulf, China

The Wutou section, hereinafter referred to as “WTS”, lies in Jiangping, Guangxi Province, China (21°32′8.25″ N, 108°06′59.9″ E; thickness of 246 cm) and consists of fluvial-lacustrine facies and dune sands of the Late Holocene. This study reconstructed the evolution of storm surges along the coast of the Beibu Gulf, Guangxi over the Little Ice Age, based on three accelerator mass spectrometry (AMS)-14C, optically stimulated luminescence (OSL) dating ages, and the analyses of grain size and heavy minerals. The analysis results indicated that the storm sediments interspersed among aeolian sands, lagoon facies, and weak soil display a coarse mean grain size and poor sorting. The storm sediments also show high maturity of heavy minerals and low stability resulting from rapid accumulation due to storm surges originating from the land-facing side of the coastal dunes. Records of seven peak storm surge periods were recorded in the WTS over the past millennium and mainly occurred after 1400 AD, i.e., during the Little Ice Age. The peaks in storm surges, including the 14Paleostrom deposit (hereinafter referred to as “Pd”) (1425–1470AD), 10Pd (1655–1690AD), 6Pd (1790–1820AD), and 4Pd (1850–1885AD) approximately corresponded with the periods of minimum sunspot activity, suggesting that the periods of storm surge peaks revealed by the WTS were probably regulated to a great extent by solar activity.