The relevance of local magnetic records when using extreme space weather events as benchmarks
Identifiers
Permanent link (URI): http://hdl.handle.net/10017/50722DOI: 10.1051/swsc/2021018
ESSN: 2115-7251
Publisher
EDP Sciences
Date
2021-06-08Funders
Ministerio de Economía y Competitividad
Bibliographic citation
Saiz, E., Cid, C. & Guerrero, A. 2021, "The relevance of local magnetic records when using extreme space weather events as benchmarks", Journal of Space Weather and Space Climate, vol. 11, art. no. 35.
Keywords
Local magnetic records
H-spikes
Extreme events
Longitudinal asymmetry
Project
info:eu-repo/grantAgreement/MINECO//AYA2016-80881-P
Document type
info:eu-repo/semantics/article
Version
info:eu-repo/semantics/publishedVersion
Publisher's version
https://doi.org/10.1051/swsc/2021018Rights
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Access rights
info:eu-repo/semantics/openAccess
Abstract
Space weather indices introduced for scientific purposes are commonly used to quantify
operational nowcast of the geospace state during extreme space weather events. Some indices, such as
the Disturbance storm time (Dst) index, have been applied to situations for which they are not originally
intended. This raises a question about suitability as a space weather benchmark. In analysing historical
records for different magnetometers at low- and mid-latitude, we find periods with longitudinal asymmetry
in magnetic response that suggest important signals from individual magnetometers are being averaged out
of the Dst record. This asymmetry develops as a double spike in the H-component: one negative in the
observatories in the day sector and one positive in the observatories in the night sector. These spikes
develop in short-time (about 2 h) and pose a potential hazardous effect for users affected by space weather.
The results from historical events have been reinforced with the systematic study of magnetic records
during extreme events (Dst 200 nT and AL 2000 nT) in the period 1998-2017 from six magnetic
observatories at about 40 magnetic latitude. Moreover, we show that the largest asymmetries take place
during the early main phase and are recorded in narrow local time sectors. An important outcome of these
results is that space weather benchmarks should be based on local records instead of the commonly used
global indices. This action improves two important aspects of space weather: the assessment of historical
extreme events and that of the needs of users.
Files in this item
Files | Size | Format |
|
---|---|---|---|
Relevance_Saiz_JSWSC_2021.pdf | 3.516Mb |
|
Files | Size | Format |
|
---|---|---|---|
Relevance_Saiz_JSWSC_2021.pdf | 3.516Mb |
|
Collections
- FISICA - Artículos [76]