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  • Article
  • Open Access

The gradient wind in the mesosphere and lower thermosphere

Earth, Planets and Space201451:BF03353234

  • Received: 10 August 1998
  • Accepted: 19 November 1999
  • Published:


HRDI zonally averaged daytime temperatures are used to compute the gradient wind in the 65–105 km range. Results are compared with independently measured HRDI zonal mean zonal winds. The gradient wind captures the essential features of the observed wind field in the summertime midlatitudes, including the stratospheric easterly (westward) jet and the reversal to westerly (eastward) winds in the lower thermosphere. The consistency between HRDI and gradient winds diminishes at tropical latitudes, due to substantial tidal contamination of daytime temperatures used to compute the gradient wind.


  • Zonal Wind
  • Vertical Wind Shear
  • Geostrophic Wind
  • Diurnal Tide
  • Lower Thermosphere