Sökning: WFRF:(Gjerloev J.) >
Distribution and Oc...
Distribution and Occurrence Frequency of dB/dt Spikes During Magnetic Storms 1980–2020
-
- Schillings, Audrey (författare)
- Umeå universitet,Institutionen för fysik,School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom
-
- Palin, L. (författare)
- Toulouse, France
-
- Opgenoorth, Hermann J. (författare)
- Umeå universitet,Institutionen för fysik,School of Physics and Astronomy, University of Leicester, Leicester, United Kingdom
-
visa fler...
-
- Hamrin, Maria, 1972- (författare)
- Umeå universitet,Institutionen för fysik
-
- Rosenqvist, L. (författare)
- Swedish Defence Research Agency, Stockholm, Sweden
-
- Gjerloev, J.W. (författare)
- JHU/APL, MD, Laurel, United States; Department of Physics and Technology, University of Bergen, Bergen, Norway
-
- Juusola, L. (författare)
- Finnish Meteorological Institute, Helsinki, Finland
-
- Barnes, R. (författare)
- JHU/APL, MD, Laurel, United States
-
visa färre...
-
(creator_code:org_t)
- John Wiley & Sons, 2022
- 2022
- Engelska.
-
Ingår i: Space Weather. - : John Wiley & Sons. - 1542-7390. ; 20:5
- Relaterad länk:
-
https://doi.org/10.1...
-
visa fler...
-
https://umu.diva-por... (primary) (Raw object)
-
https://urn.kb.se/re...
-
https://doi.org/10.1...
-
visa färre...
Abstract
Ämnesord
Stäng
- The physical magnetospheric cause for geomagnetically induced currents (GICs) are rapid time-varying magnetic fields (dB/dt), which occur mainly during magnetic substorms and storms. When, where and why exactly such rapid dB/dt may occur is insufficiently understood. We investigated all storms since 1980 and analyzed the negative and positive dB/dt spikes (>|500| nT/min) in the north and east component using a worldwide coverage (SuperMAG). Our analysis confirmed the existence of two dB/dt spikes "hotspots" located in the pre-midnight and in the morning magnetic local time sector, independently of the geographic location of the stations. The associated physical phenomena are probably substorm current wedge onsets and westward traveling surges (WTS) in the evening sector, and wave- or vortex-like current flows in the morning sector known as Omega bands. We observed a spatiotemporal evolution of the negative northern dB/dt spikes. The spikes initially occur in the pre-midnight sector, and then develop in time toward the morning sector. This spatiotemporal sequence is correlated with bursts in the AE index, and can be repeated several times throughout a storm. Finally, we investigated the peak value of Dst and AE during the storm period in comparison with the dB/dt spike occurrence frequency, we did not find any correlation. This result implies that a moderate storm with many spikes can be as (or more) dangerous for ground-based infrastructures than a major storm with fewer dB/dt spikes. Our findings regarding the physical causes and characteristics of dB/dt spikes may help to improve the GIC forecast for the affected regions.
Ämnesord
- NATURVETENSKAP -- Fysik -- Astronomi, astrofysik och kosmologi (hsv//swe)
- NATURAL SCIENCES -- Physical Sciences -- Astronomy, Astrophysics and Cosmology (hsv//eng)
Nyckelord
- dB/dt spikes
- geomagnetic storms
- GICs
- Omega bands
- space weather
- substorm current wedge
Publikations- och innehållstyp
- ref (ämneskategori)
- art (ämneskategori)
Hitta via bibliotek
Till lärosätets databas