Journal cover Journal topic
Annales Geophysicae An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 1.621 IF 1.621
  • IF 5-year value: 1.614 IF 5-year 1.614
  • CiteScore value: 1.61 CiteScore 1.61
  • SNIP value: 0.900 SNIP 0.900
  • SJR value: 0.910 SJR 0.910
  • IPP value: 1.58 IPP 1.58
  • h5-index value: 24 h5-index 24
  • Scimago H index value: 80 Scimago H index 80
Volume 35, issue 1
Ann. Geophys., 35, 161-170, 2017
https://doi.org/10.5194/angeo-35-161-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

Special issue: The 14th International Symposium on Equatorial Aeronomy

Ann. Geophys., 35, 161-170, 2017
https://doi.org/10.5194/angeo-35-161-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

Regular paper 30 Jan 2017

Regular paper | 30 Jan 2017

Climatology of thermospheric neutral winds over Oukaïmeden Observatory in Morocco

Mohamed Kaab1, Zouhair Benkhaldoun1, Daniel J. Fisher2, Brian Harding2, Aziza Bounhir1, Jonathan J. Makela2, Amine Laghriyeb1, Khalifa Malki1, Ahmed Daassou1, and Mohamed Lazrek1 Mohamed Kaab et al.
  • 1Oukaimeden Observatory, Laboratoire de Physique des Hautes Energies et Astrophysique, FSSM, Cadi Ayyad University, Marrakech, Morocco
  • 2Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA

Abstract. In order to explore coupling between the thermosphere and ionosphere and to address the lack of data relating to thermospheric neutral winds and temperatures over the African sector, a new system of instruments was installed at the Oukaïmeden Observatory located in the high Atlas Mountains, 75km south of Marrakesh, Morocco (31.206°N, 7.866°W, 22.84°N magnetic). In this work we present the first multi-year results of the climatology of meridional and zonal winds obtained during the period from January 2014 to February 2016, including observations from 648 nights. The measurements are obtained using an imaging Fabry–Pérot interferometer, which measures the 630.0nm emissions caused by dissociative recombination of O2+. The basic climatology of the winds is as expected, showing zonal winds that are strongly eastward in the early evening just after sunset with a speed of 50 to 100ms−1 decreasing in magnitude, and reversing directions in the local summer months, towards sunrise. The meridional winds are slightly poleward in the early evening during the local winter, before reversing directions around 21:00LT. In the local summer months, the meridional winds are equatorward for the entire night, reaching a maximum equatorward speed of 75ms−1. We compare the observed climatologies of neutral winds to that provided by the recently updated Horizontal Wind Model (HWM14) in order to validate that model's predictions of the thermospheric wind patterns over the eastern portion of Africa. The model captures much of the features in the observational climatologies. The most notable exception is for the zonal winds during local summer, when the maximum eastward wind in the observations occurs approximately 4h later than seen in the model results.

Publications Copernicus
Special issue
Download
Short summary
we present the first multi-year results of the climatology of horizontal winds obtained during a period of 26 months. We compare the observed climatologies of neutral winds to that provided by the recently updated Horizontal Wind Model (HWM14) in order to validate that model's predictions of the thermospheric wind patterns over the eastern portion of Africa. HWM14 generally compares well with the horizontal winds, but significant magnitude and phase differences remain in certain seasons.
we present the first multi-year results of the climatology of horizontal winds obtained during a...
Citation
Share