GEOSCAN Search Results: Fastlink


TitleA link between high-speed solar wind streams and explosive extratropical cyclones
AuthorPrikryl, P; Iwao, K; Muldrew, D B; Rusin, V; Rybansky, M; Bruntz, R
SourceJournal of Atmospheric and Solar-Terrestrial Physics vol. 149, (2016), 2016 p. 219-231,
Alt SeriesEarth Sciences Sector, Contribution Series 20150487
Mediapaper; on-line; digital
File formatpdf
Subjectsextraterrestrial geology; storms; geomagnetic fields; geomagnetic variations; magnetic storms; auroral zone; magnetosphere; ionosphere; solar variations; high-speed solar wind stream; co-rotating interaction region; atmospheric gravity waves; extratropical cyclone; solar winds; weather; troposphere; interplanetary magnetic field
Illustrationslocation maps; graphs; bar graphs
ProgramNorthern Canada Geohazards Project, Public Safety Geoscience
AbstractA link between solar wind magnetic sector boundary (heliospheric current sheet) crossings by the Earth and the upper-level tropospheric vorticity was discovered in the 1970s. These results have been later confirmed but the proposed mechanisms remain controversial. Using a database of extratropical cyclones tracks obtained from two meteorological reanalysis datasets, superposed epoch analysis of time series of solar wind plasma parameters and the green coronal emission line intensity keyed by times of maximum growth of explosively developing extratropical cyclones is performed. The new statistical evidence corroborate the previously published results indicating that explosive extratropical cyclones tend to occur after arrivals of solar wind disturbances such as high-speed solar wind streams from coronal holes when large amplitude magneto-hydrodynamic waves couple to the magnetosphere-ionosphere system and modulate Joule heating and/or Lorentz forcing of the high-latitude thermosphere generating medium-scale atmospheric gravity waves. These aurorally-generated gravity waves propagate energy upward and downward through the atmosphere. At tropospheric level, in spite of significantly reduced amplitudes, they could provide a lift of unstable air to release the moist symmetric instability thus initiating slantwise convection and forming cloud/precipitation bands. The release of latent heat is known to provide energy for rapid development and intensification of extratropical cyclones.
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 a possible influence of solar wind disturbances on the lower atmosphere affecting tropospheric weather.