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TitleAssessment of extreme values in geomagnetic and geoelectric field variations for Canada
AuthorNikitina, L V; Trichtchenko, L D; Boteler, D H
SourceSpace Weather vol. 14, issue 7, 2016 p. 481-494,
Alt SeriesEarth Sciences Sector, Contribution Series 20160083
Mediapaper; on-line; digital
File formatpdf
NTS72E; 72L; 72M; 73D; 73E; 73L; 73M; 74D; 74E; 74L; 74M; 82A; 82H; 82I; 82O; 82P; 83; 84
Lat/Long WENS-120.0000 -110.0000 60.0000 49.0000
Subjectsgeophysics; remote sensing; geomagnetism; geomagnetic fields; geomagnetic variations; geoelectric variations
Illustrationstables; plots; graphs
ProgramNorthern Canada Geohazards Project, Public Safety Geoscience
AbstractDisturbances of the geomagnetic field produced by space weather events can have an impact on power systems and other critical infrastructure. To mitigate these risks it is important to determine the extreme values of geomagnetic activity that can occur. More than 40 years of 1-minute magnetic data recorded at thirteen Canadian geomagnetic observatories have been analyzed to evaluate extreme levels in geomagnetic and geoelectric activity in different locations of Canada. The hourly ranges of geomagnetic field variations and hourly maximum in rate of change of the magnetic variations have been used as measures of geomagnetic activity. Geoelectric activity is estimated by the hourly peak amplitude of the geoelectric fields calculated with use of Earth resistivity models specified for different locations in Canada. A generalized extreme value distribution was applied to geomagnetic and geoelectric indices to evaluate extreme geomagnetic and geoelectric disturbances which could happen once per 50 and once per 100 years with 99% confidence interval. Influence of geomagnetic latitude and Earth resistivity models on the results for the extreme geomagnetic and geoelectric activity is discussed. The extreme values provide criteria for assessing the vulnerability of power systems and other technology to geomagnetic activity for design or mitigation purposes.
Summary(Plain Language Summary, not published)
Space weather refers to the dynamic conditions on the Sun and in the space environment, in particular, in the near-Earth environment, that can affect critical infrastructure. NRCan operates the Canadian Space Weather Forecast Centre and conducts research into space weather effects on power systems, pipelines, radio communications and GNSS positioning to help Canadian industry understand and mitigate the effects of space weather. This paper examines extreme geomagnetic and geoelectric disturbances which could happen during extreme space weather events and affect power systems at different locations in Canada. Statistical analysis is applied to data from thirteen geomagnetic observatories across Canada and provides local levels of extreme values of geomagnetic variations and geoelectric fields which could happen once per 50 and once per 100 years. This assessment aimed to be used to help power companies to mitigate risks from space weather events.