| Title | Preconditioning of interplanetary space due to transient CME disturbances |
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| Author | Temmer, M; Reiss, M A; Nikolic, L; Hofmeister, S J; Veronig, A M |
| Source | The Astrophysical Journal vol. 835, no. 2, 141, 2017 p. 1-6, https://doi.org/10.3847/1538-4357/835/2/141  Open Access |
| Image |  |
| Year | 2017 |
| Alt Series | Natural Resources Canada, Contribution Series 20180463 |
| Publisher | American Astronomical Society |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf (Adobe® Reader®); html |
| Subjects | geophysics; extraterrestrial geology; models; geomagnetism; geomagnetic fields; magnetic storms; Forecasting |
| Illustrations | time series; bar graphs; tables; plots |
| Program | Public Safety Geoscience Northern Canada Geohazards Project |
| Released | 2017 01 24 |
| Abstract | Interplanetary space is characteristically structured mainly by high-speed solar wind streams emanating from coronal holes and transient disturbances such as coronal mass ejections (CMEs). While
high-speed solar wind streams pose a continuous outflow, CMEs abruptly disrupt the rather steady structure, causing large deviations from the quiet solar wind conditions. For the first time, we give a quantification of the duration of disturbed
conditions (preconditioning) for interplanetary space caused by CMEs. To this aim, we investigate the plasma speed component of the solar wind and the impact of in situ detected interplanetary CMEs (ICMEs), compared to different background solar wind
models (ESWF, WSA, persistence model) for the time range 2011-2015. We quantify in terms of standard error measures the deviations between modeled background solar wind speed and observed solar wind speed. Using the mean absolute error, we obtain an
average deviation for quiet solar activity within a range of 75.1-83.1 km/s. Compared to this baseline level, periods within the ICME interval showed an increase of 18%-32% above the expected background, and the period of two days after the ICME
displayed an increase of 9%-24%. We obtain a total duration of enhanced deviations over about three and up to six days after the ICME start, which is much longer than the average duration of an ICME disturbance itself (~1.3 days), concluding that
interplanetary space needs ~2-5 days to recover from the impact of ICMEs. The obtained results have strong implications for studying CME propagation behavior and also for space weather forecasting. |
| 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. The interaction of the solar wind and coronal mass ejections (CME) with the Earth's magnetic field can affect the intensity and direction of the magnetic field. In this paper we investigate the duration of
disturbed conditions for interplanetary space caused by CMEs. |
| GEOSCAN ID | 314576 |
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