Information Abstract Text Hysteresis effect between geomagnetic activity indices (Ap, Dst) and interplanetary medium parameters in solar activity cycles 21–24
Journal Title: Solar-Terrestrial Physics - Year 2023, Vol 9, Issue 3
Abstract
We have studied the relationship of geomagnetic activity indices (Ap, Dst) on time intervals, equal to solar cycles (∼11 years), with solar activity indicators and heliospheric parameters. It is shown that the plots of the Ap and Dst indices versus solar activity indicators, as well as versus heliospheric parameters, i.e. solar wind and IMF parameters in the ascending and descending phases of solar activity cycles 21–24 do not coincide, which is indicative of the hysteresis phenomenon. The Ap and Dst indices form hysteresis loops with all parameters we analyze during cycles 21–24. The shape and area of the hysteresis loops, as well as the direction of rotation, clockwise or counterclockwise, depend significantly on indicators of solar activity, heliospheric parameters and change from cycle to cycle. We have found a tendency for the extension and area of the hysteresis loops to decrease from cycle 21 to cycle 24. Analysis of the variability in the shape and size of the hysteresis loops formed by the Ap and Dst indices with solar indicators and heliospheric parameters gives reason to believe that the obtained loops reflect the long-term evolution of the solar wind energy flux, which determines global geomagnetic activity and the magnetospheric ring current intensity in the ascending and descending phases of solar activity cycles 21‒24.
Authors and Affiliations
Kurazhkovskaya N. A. , Kurazhkovskii A. Y.
INVERSION OF BACKSCATTER IONOGRAMS INTO QUASIPARABOLIC IONOSPHERIC LAYER PARAMETERS
We present an inversion scheme of the backscatter signal leading edge into parameters of the quasi-parabolic electron density profile, which is based on the comparison of experimental and calculated minimum delays of sca...
Solar activity and Earth seismicity
Using the results of continuous long-term observations over 50 years (including solar cycles 20–24), we study the relationship between Earth’s seismicity and solar activity. An increase in the number of strong earthquake...
DIAGNOSTICS OF EMISSION INTENSITIES AND ELECTRON DENSITY IN AURORAS BASED ON EMPIRICAL PRECIPITATION MODELS
We have studied the influence of the precipitating electron spectrum shape on the integral intensity of emissions λ391.4 nm 1NG N⁺₂, λ670.4 mn 1PG N₂, λ337.1 nm 2PG N₂, λ320.0 nm VK N₂, λ127.3 nm LBH N₂, atomic oxygen em...
INTERACTIVE COMPUTER MODEL FOR AURORA FORECAST AND ANALYSIS
An interactive computer model of a short-term (with a horizon 30–70 min) forecast of aurora intensity has been developed in the form of a web-based geoinformation system. The OVATION-Prime empirical model is used as the...
Heating manifestations at the onset of the 29 June 2012 flare
Analysis of GOES data for the SOL2012-06-29T04:09 flare, class C4.6, shows a thermal character of the energy release for several minutes before the impulsive stage. Plasma heating to temperatures above 10 MK leads to the...