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Monthly Backward Trajectory Map



Backward Trajectory of Air Mass reaching
Hong Kong in


Backward Trajectory Map

Points to note:

  • The above diagram shows all daily (past 72-hour) backward trajectories of air mass reaching Hong Kong at a height of 100 metres above ground level within the selected month.
  • The product may be useful for tracing the origin of air mass reaching Hong Kong.  Please click here for cases of the backward trajectory map under different weather patterns.
  • Monthly maps will be updated on the first day of the following months.
  • The trajectory was prepared using the HYSPLIT model of NOAA. Anyone wishing to quote or further disseminate the data should read the "Disclaimer" of the NOAA Air Resources Laboratory web site for details.

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Last revision date: <21 Dec 2012>