Neyo: A katabatic dry wind

  • Hassan Addom
  • Ammar Gaber
  • Abulgasim Idris
Keywords: Darfur, nocturnal radiation, katabatic flow, dehydration


The objective of this study is to explain how the Neyo wind stream develops and how it can damage crops and endanger people’s lives in the Darfur Region of Sudan. Due to lack of official meteorological observations, the data was retrieved from NOAA Air Resources Laboratory (ARL) used by the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT). Three scenarios for katabatic flow were formulated. Forces acting on air parcels were calculated for different slope angles. HYSPLIT vertical soundings revealed a reservoir of dry air over the area. Air parcels moving down slope allow dry air to flow across the thermal inversion layer. Due to the moisture deficit between the down flowing air and the humid grass surface, the leaves get dehydrated.


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