An Empirical Model of Vertical Plasma Drift Over the African Sector

作者:Dubazane Makhosonke Berthwell; Habarulema John Bosco*
来源:Space Weather-The International Journal of Research and Applications, 2018, 16(6): 619-635.
DOI:10.1029/2018SW001820

摘要

Daytime vertical E x B drift can be derived from difference of H-component magnetic field measurements (Delta H) using a pair of low-latitude and equatorial latitude magnetometer stations. Knowledge of E x B drift is of utmost importance in space weather-related predictions since it can significantly affect ionospheric density structures and dynamics. For the first time, we developed a quantitative relationship between equatorial electrojet (Delta H) and vertical E x B drift over the African region using magnetometer data and E x B drift observations from the Communication and Navigation Outage Forecasting System (C/NOFS) satellite during local daytime (0700-1800 LT) from 2008 to 2013 when magnetometer data were available. Additionally, we have constructed vertical E x B drift models over the African sector based on C/NOFS vertical E x B drift data and relevant physical and geophysical inputs. Validating using data not included in model development, our model estimated C/NOFS vertical E x B drift with correlation coefficient values of 0.85 and 0.56 during quiet and disturbed conditions, respectively. The daily pattern of the E x B drift velocity is consistent between the developed model based on C/NOFS data and the climatological Scherliess-Fejer model. However, the Scherliess-Fejer model generally overestimated C/NOFS vertical E x B drift (in most cases) with a correlation coefficient of 0.54 during quiet conditions.

  • 出版日期2018-6