Abstract. The present work explores the ionospheric and thermospheric responses to the 27–28 February 2014 geomagnetic storm. For the first time, a geomagnetic storm is explored in north Africa using interferometer, all-sky imager and GPS data. This storm was due to the arrival at the Earth of the shock of a coronal mass ejection (CME) associated with the solar flare event on 25 February 2014. A Fabry–Perot interferometer located at the Oukaïmeden Observatory (31.206° N, 7.866° W; 22.84° N magnetic) in Morocco provides measurements of the thermospheric neutral winds based on observations of the 630 nm red line emission. A wide-angle imaging system records images of the 630 nm emission. The effects of this geomagnetic storm on the thermosphere are evident from the clear departure of the neutral winds from their seasonal behavior. During the storm, the winds experience an intense and steep equatorward flow from 21:00 to 01:00 LT and a westward flow from 22:00 to 03:00 LT. The equatorial wind speed reaches a maximum of 120 m s−1 for the meridional component at 22:00 LT, after the zonal wind reverses to the westward direction. Shortly after 00:00 LT a maximum westward speed of 80 m s−1 was achieved for the zonal component of the wind. The features of the winds are typical of traveling atmospheric disturbance (TAD)-induced circulation; the first TAD coming from the Northern Hemisphere reaches the site at 21:00 LT and a second one coming from the Southern Hemisphere reaches the site at about 00:00 LT. We estimate the propagation speed of the northern TAD to be 550 m s−1. We compared the winds to the DWM07 (Disturbance Wind Model) prediction model and find that this model gives a good indication of the new circulation pattern caused by storm activity, but deviates largely inside the TADs. The effects on the ionosphere were also evident through the change observed in the background electrodynamics from the reversal in the drift direction in an observed equatorial plasma bubble (EPB). Total electron content (TEC) measurements of a GPS station installed in Morocco, at Rabat (33.998° N, 6.853° W), revealed a positive storm.

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, 75 km 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 630.0 nm emissions caused by dissociative recombination of O + 2 . 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 100 m s −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 21:00 LT. In the local summer months, the meridional winds are equatorward for the entire night, reaching a maximum equatorward speed of 75 m s −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 4 h later than seen in the model results.

In this paper, we have used the National Centers for Environmental Prediction (NCEP)/National Centers for Atmospheric Research (NCAR) Reanalysis data base to study, first, a comparison between balloon sounding made at different stations with coinciding model‐based meteorological analysis. The comparison allows the assessment of reliability of the analysis in the studied period and to highlight NCEP/NCAR Reanalysis as an interesting data base for site characterization. Using the same system of Reanalysis, we present, secondly, the first complete characterization of main meteorological parameters at Oukaïmeden Observatory: wind speed, its direction, temperature and pressure. The statistical treatment of data will cover the years between 1990 and 2009. Monthly, seasonal and annual results are analysed. The comprehensive and reliable statistics of tropospheric wind speeds at Oukaïmeden are presented. We found a clear annual periodicity of 200 mbar wind speed. This periodicity could be related to the seasonal dependence of seeing that is affected by the existence of cloud sea during the period around autumn–winter and by high wind speed regimes during spring. The connection of high‐ to low‐altitude tropospheric winds has been explored. We found a high correlation comparable to the ones found at La Silla and La Palma sites. The local parameters in particular topography and stratocumulus formations might affect 700 mbar wind roses. Richardson numbers  calculated for each month at Oukaïmeden and La Palma are presented. By analysing the  values, we found out that the periods and the regions of development of turbulence in relative terms of stability for the two locations are very similar. In addition, we present the first example of a  profile estimated from NCEP/NCAR Reanalysis. We found that this profile presents a tendency very similar to the same averaged profile measured by the balloon‐born radiosondes.

Abstract. The present work explores the ionospheric and thermospheric responses to the 27–28 February 2014 geomagnetic storm. For the first time, a geomagnetic storm is explored in north Africa using interferometer, all-sky imager and GPS data. This storm was caused by coronal mass ejection (CME) associated flares that occurred on 25 February 2014. A Fabry-Perot interferometer located at the Oukaimeden Observatory (31.206° N, 7.866° W, 22.84° N magnetic) in Morocco provides measurements of the thermospheric neutral winds based on the observations of the 630 nm redline emission. A wide angle imaging system records images of the 630-nm emission. The effects of this geomagnetic storm on the thermosphere are evident from the clear departure of the neutral winds from their seasonal behavior. During the storm, the winds experience an intense and steep equatorward flow from 21 to 01 LT and a westward flow from 22 to 03 LT. The equatorial wind speed reaches a maximum of 120 m/s for the meridional component at 22 LT, when the zonal wind reverses to the westward direction. Shortly after 00 LT a maximum westward speed of 80 m/s was achieved for the zonal component of the wind. The features of the winds are typical of TAD (Traveling Atmospheric Disturbances) induced circulation; the first TAD coming from the northern hemisphere reaches the site at 21 LT and a second one coming from the southern hemisphere reaches the site at about 00 LT. We estimate the propagation speed of the northern TAD to be 550 m/s. We compared the winds to DWM07 (Disturbance Wind Model) prediction model and find that this model gives a good indication of the new circulation pattern caused by storm activity, but deviates largely inside the TADs. The effects on the ionosphere were also evident through the change observed in the background electrodynamics from the reversal in drift direction in an observed equatorial plasma bubble. TEC measurements of a GPS station installed in Morocco, at Rabat (33.998° N; 6.853° W, geographic) revealed a positive storm.

This paper aims at studying the wind at 200 mbar over the Moroccan observatory Oukaimeden, as high‐altitude winds have been adopted as a useful parameter for site characterization in terms of the suitability of a site for the development of some adaptive optics techniques. The data used come from the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data base, which is widely acknowledged as being reliable. Statistical analyses of 200‐mbar wind speed since 1983 are performed. Comparison with some of the main observatory sites worldwide qualifies Oukaimeden as one of the best observatory sites in terms of 200‐mbar wind statistics. Our analysis of a record of seeing measurements during the years 2003 and 2004 concludes that while 200‐mbar wind speed can be used as a parameter for ranking astronomical sites in term of their suitability for adaptive optics, it cannot be used for the whole atmospheric seeing prediction. A comparison of monthly values of the seeing parameter at Oukaimeden, La Silla and Paranal demonstrates the high seeing quality of Oukaimeden, as the seeing values measured were lower than those of La Silla and Paranal for most of the time during the comparison period. Furthermore, a statistical analysis of atmospheric stratified seeing, wavefront coherence time and isoplanatic angle measured with a Multi‐Aperture Scintillation Sensor instrument over Paranal from 2004 to 2007 have been performed. We found good correlations between 200‐mbar wind velocity and levels 4, 5 and 6 seeing, wavefront coherence time and isoplanatic angle, with corresponding correlation coefficients of 0.74, 0.79, 0.70, 0.97 and 0.78.