Open-ended, high cadence, Kp-like geomagnetic index Hp

Mapping Intimacies ◽

10.5194/egusphere-egu2020-6646 ◽

2020 ◽

Author(s):

Jürgen Matzka ◽

Guram Kervalishvili ◽

Jan Rauberg ◽

Claudia Stolle ◽

Yosuke Yamazaki

Keyword(s):

Solar Wind ◽

Frequency Distribution ◽

Temporal Resolution ◽

Geomagnetic Activity ◽

Space Weather ◽

Energy Input ◽

Geomagnetic Index ◽

High Cadence

An open-ended, high cadence, Kp-like geomagnetic index, called Hp index, is developed within the H2020 project SWAMI (Space Weather Atmosphere Models and Indices). The traditional Kp index is an excellent measure for energy input by the solar wind and is widely used in space weather science and applications. The new planetary index Hp resembles the Kp index by having a similar derivation scheme and a nearly identical frequency distribution of index values. Hp is available from 1995 onward with different time resolutions, e.g., 30 minutes and 60 minutes, and thus provides a higher temporal resolution than the 3-hourly Kp index. Additionally, events with Hp > 9- were further subdivided using an open-ended scale (9o, 9+, 10-, 10o, 10+, 11-, ...) to represent the highest levels of geomagnetic activity with higher resolution.

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The open-ended, high cadence, Kp-like geomagnetic Hp30 and Hp60 indices

10.5194/egusphere-egu21-2846 ◽

2021 ◽

Author(s):

Guram Kervalishvili ◽

Jürgen Matzka ◽

Claudia Stolle ◽

Jan Rauberg

Keyword(s):

European Union ◽

Real Time ◽

Frequency Distribution ◽

Temporal Resolution ◽

Geomagnetic Activity ◽

Space Weather ◽

Research Activity ◽

Different Levels ◽

High Cadence ◽

Index Family

<div>The new planetary open-ended Hpo index family (consisting of the half-hourly Hp30 and hourly Hp60) has been developed within the Space Weather Atmosphere Models and Indices (SWAMI) project (see http://swami-h2020.eu/) of the H2020 European Union research activity. These new indices resemble the Kp index by having a similar derivation scheme and a nearly identical frequency distribution of index values for events with values < 9. However, they have provided a better temporal resolution than the 3-hourly Kp index. Additionally, the events with values > 9- are further subdivided using an open-ended scale (9o, 9+, 10-, 10o, 10+, 11-, ...) to better represent different levels of strong geomagnetic activity. In this study, the advantages and integrity of Hp30 and Hp60 indices are analysed and discussed. The comparison of these indices with the 3-hourly Kp index in terms of frequency distribution and correlation and with other geophysical parameters are also presented.</div><div>Near real-time indices and archive indices back to 1995 are available from GFZ under the CC BY 4.0 license including linear versions of the Hp30 and Hp60 indices, the ap30 and ap60 indices (see https://www.gfz-potsdam.de/en/section/geomagnetism/data-products-services/hpo-index/). Near real-time&#160;plots of the Hp30, Hp60 and Kp indices for the current day and the previous six days are also provided.</div>

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Explicit IMF By-dependence in geomagnetic activity

10.5194/egusphere-egu21-850 ◽

2021 ◽

Author(s):

Lauri Holappa ◽

Timo Asikainen ◽

Kalevi Mursula

Keyword(s):

Solar Wind ◽

Geomagnetic Activity ◽

Space Weather ◽

High Latitude ◽

Coupling Function ◽

Future Space ◽

Weather Modeling ◽

Southern High Latitude ◽

Imf Clock Angle ◽

The Imf

The interaction of the solar wind with the Earth&#8217;s magnetic &#64257;eld produces geomagnetic activity, which is critically dependent on the orientation of the interplanetary magnetic &#64257;eld (IMF). Most solar wind coupling functions quantify this dependence on the IMF orientation with the so-called IMF clock angle in a way, which is symmetric with respect to the sign of the By component. However, recent studies have shown that IMF By is an additional, independent driver of high-latitude geomagnetic activity, leading to higher (weaker) geomagnetic activity in Northern Hemisphere (NH) winter for By > 0 (By < 0). For NH summer the dependence on the By sign is reversed. We quantify the size of this explicit By-e&#64256;ect with respect to the solar wind coupling function, both for northern and southern high-latitude geomagnetic activity. We show that for a given value of solar wind coupling function, geomagnetic activity is about 40% stronger for By > 0 than for By < 0 in NH winter. We also discuss recent advances in the physical understanding of the By-effect. Our results highlight the importance of the IMF By-component for space weather and must be taken into account in future space weather modeling.

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Seasonal and diurnal variations of geomagnetic activity and their role in Space Weather forecast

Canadian Journal of Physics ◽

10.1139/p01-049 ◽

2001 ◽

Vol 79 (6) ◽

pp. 907-920 ◽

Cited By ~ 6

Author(s):

W Lyatsky ◽

A M Hamza

Keyword(s):

Solar Wind ◽

Seasonal Variation ◽

Diurnal Variation ◽

Geomagnetic Activity ◽

Space Weather ◽

Weather Forecast ◽

Diurnal Variations ◽

Ionospheric Conductivity ◽

Solar Wind Parameters ◽

Possible Cause

A possible test for different models explaining the seasonal variation in geomagnetic activity is the diurnal variation. We computed diurnal variations both in the occurrence of large AE (auroral electrojet) indices and in the AO index. (AO is the auroral electrojet index that provides a measure of the equivalent zonal current.) Both methods show a similar diurnal variation in geomagnetic activity with a deep minimum around (37) UT (universal time) in winter and a shallower minimum near 59 UT in equinoctial months. The observed UT variation is consistent with the results of other scientists, but it is different from that expected from the RussellMcPherron mechanism proposed to explain the seasonal variation. It is suggested that the possible cause for the diurnal and seasonal variations may be variations in nightside ionospheric conductivity. Recent experimental results show an important role for ionospheric conductivity in particle acceleration and geomagnetic disturbance generation. They also show that low ionospheric conductivity is favorable to the generation of auroral and geomagnetic activity. The conductivity in conjugate nightside auroral zones (where substorm generation takes place) is minimum at equinoxes, when both auroral zones are in darkness. The low ionospheric conductivity at equinoxes may be a possible cause for the seasonal variation in the geomagnetic activity with maxima in equinoctial months. The diurnal variation in geomagnetic activity can be produced by the UT variation in the nightside ionospheric conductivity, which in winter and at equinoxes has a maximum around 45 UT that may lead to a minimum in geomagnetic activity at this time. We calculated the correlation patterns for the AE index versus solar-wind parameters inside and outside the (27) UT sector related to the minimum in geomagnetic activity. The correlation patterns appear different in these two sectors indeed, which is well consistent with the UT variation in geomagnetic activity. It also shows that it is possible to improve significantly the reliability of the Space Weather forecast by taking into account the dependence of geomagnetic activity not only on solar-wind parameters but also on UT and season. Our test shows that a simple account for the dependence of geomagnetic activity on UT can improve the reliability of the Space Weather forecast by at least 50% in the 27 UT sector in winter and equinoctial months. PACS No.: 91.25Le

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Study of the Influence of the Solar Wind Energy on the Geomagnetic Activity for Space Weather Science

The Astrophysical Journal ◽

10.3847/1538-4357/ab91b9 ◽

2020 ◽

Vol 896 (2) ◽

pp. 149 ◽

Cited By ~ 2

Author(s):

Daniele Telloni ◽

Francesco Carbone ◽

Ester Antonucci ◽

Roberto Bruno ◽

Catia Grimani ◽

...

Keyword(s):

Solar Wind ◽

Wind Energy ◽

Geomagnetic Activity ◽

Space Weather ◽

Solar Wind Energy

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Is Our Understanding of Solar-Wind/Magnetosphere Coupling Satisfactory?

Frontiers in Astronomy and Space Sciences ◽

10.3389/fspas.2021.634073 ◽

2021 ◽

Vol 8 ◽

Author(s):

Joseph E. Borovsky

Keyword(s):

Solar Wind ◽

Geomagnetic Activity ◽

Space Weather ◽

Unsolved Problem ◽

Solar Wind Plasma ◽

Space Physics ◽

Geomagnetic Indices ◽

Ionosphere Model ◽

Fundamental Understanding ◽

Full Knowledge

An assessment of our physics-based understanding of solar-wind/magnetosphere coupling finds that the understanding is not complete. Solar-wind/magnetosphere coupling is foundational to magnetospheric physics and it is a key to comprehending and predicting space weather. We are modestly successful at correlating solar-wind variables with geomagnetic indices, but we lack the full knowledge to describe in detail how the shocked solar-wind plasma transports mass, momentum, and energy into the magnetosphere-ionosphere system and how the shocked solar wind drives geomagnetic activity and magnetospheric evolution. The controlling solar-wind factors that govern the driving of the magnetosphere-ionosphere system are not accurately known. Without this knowledge accurate predictions of the magnetospheric behavior cannot be made and no magnetosphere-ionosphere model will work correctly if it is driven incorrectly. Further, without a fundamental understanding, the prediction of the system reaction to some as-yet-unseen extreme solar-wind conditions will not be possible. In this perspective article several gaps in our knowledge are cataloged. The deficiencies in our physical understanding of solar-wind/magnetosphere coupling constitute a major unsolved problem for space physics (and for astrophysics), a problem that demands enhanced, coordinated research.

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Coronal shocks associated with CMEs and flares and their space weather consequences

Proceedings of the International Astronomical Union ◽

10.1017/s1743921309029093 ◽

2008 ◽

Vol 4 (S257) ◽

pp. 61-63

Author(s):

Marina Laskari ◽

Panagiota Preka-Papadema ◽

Constantine Caroubalos ◽

George Pothitakis ◽

Xenophon Moussas ◽

...

Keyword(s):

Solar Wind ◽

Geomagnetic Activity ◽

Space Weather ◽

Geophysical Data ◽

Radio Bursts ◽

Type Ii ◽

Geomagnetic Indices ◽

Complex Events ◽

Solar Wind Parameters ◽

Solar Energetic Events

AbstractWe study the geoeffectiveness of a sample of complex events; each includes a coronal type II burst, accompanied by a GOES SXR flare and LASCO CME. The radio bursts were recorded by the ARTEMIS-IV radio spectrograph, in the 100-650 MHz range; the GOES SXR flares and SOHO/LASCO CMEs, were obtained from the Solar Geophysical Data (SGD) and the LASCO catalogue respectively. These are compared with changes of solar wind parameters and geomagnetic indices in order to establish a relationship between solar energetic events and their effects on geomagnetic activity.

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Explicit IMF By-dependence in geomagnetic activity

10.5194/egusphere-egu2020-3367 ◽

2020 ◽

Author(s):

Lauri Holappa ◽

Timo Asikainen ◽

Kalevi Mursula

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Geomagnetic Activity ◽

Space Weather ◽

High Latitude ◽

Coupling Function ◽

Ionospheric Conductivity ◽

Future Space ◽

Southern High Latitude ◽

The Imf

The interaction of the solar wind with the Earth&#8217;s magnetic field produces geomagnetic activity, which is critically dependent on the orientation of the interplanetary magnetic field (IMF). Most solar wind coupling functions quantify this dependence on the IMF orientation with the so-called IMF clock angle in a way, which is symmetric with respect to the sign of the By component. However, recent studies have shown that IMF By is an additional, independent driver of high-latitude geomagnetic activity, leading to higher (weaker) geomagnetic activity in Northern Hemisphere (NH) winter for By > 0 (By < 0). For NH summer the dependence on the By sign is reversed. We quantify the size of this explicit By-effect with respect to the solar wind coupling function, both for northern and southern high-latitude geomagnetic activity. We show that for a given value of solar wind coupling function, geomagnetic activity is about 40% stronger for By > 0 than for By < 0 in NH winter. The physical mechanism of the By-effect is not yet fully understood. Here we show that IMF By modulates the flux of energetic electrons precipitating into the ionosphere which likely modulates the ionospheric conductivity and, thus, geomagnetic activity. Our results highlight the importance of the IMF By-component for space weather and must be taken into account in future space weather modeling.

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Star Wars? Space Weather and Electricity Market: Evidence from China

Energies ◽

10.3390/en14175281 ◽

2021 ◽

Vol 14 (17) ◽

pp. 5281

Author(s):

Tong Wu ◽

Zhe You ◽

Mengqi Gong ◽

Jinhua Cheng

Keyword(s):

Solar Wind ◽

Wind Speed ◽

Space Weather ◽

Electricity Market ◽

Power Plants ◽

Consumption Rate ◽

Solar Wind Speed ◽

Electricity Consumption ◽

Coal Consumption ◽

Geomagnetic Index

This paper aims to investigate the impact of space weather on China’s electricity market. Based on data products provided by NOAA and the National Energy Administration in China, this paper uses solar wind velocity as a solar weather indicator and the disturbance storm time index as a magnetospheric weather indicator to match monthly Chinese electricity market data over 10 years. Based on a VAR model, we found that (1) space weather increases the demand for electricity in China, and solar wind speed and the geomagnetic index increase the electricity consumption of the whole of Chinese society, as space weather mainly increases the electricity consumption of the secondary and industrial sectors. (2) The geomagnetic index significantly promotes power station revenue. (3) Space weather is associated with increased energy consumption. The geomagnetic index significantly increases the coal consumption rate of fossil power plants in China, but the solar wind speed has nothing to do with the coal consumption rate of fossil power plants.

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