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Sand and Dust Weather Information



A sandstorm or duststorm is a meteorological phenomenon usually caused by strong and turbulent winds blowing over loose soil or sand and sweeping up large quantities of sand or dust particles from the ground, clouding the air and reducing the visibility drastically. In general, sandstorm/duststorm can be defined as an ensemble of particles of sand and dust energetically lifted to great heights by a strong and turbulent wind bringing visibility down to less than 1,000 metres. If the visibility is observed to be 1,000 metres or greater it would be defined as sand or dust.

There are several tools for monitoring sand and dust weather, including (a) the latest reports on sand and dust weather, (b) satellite pictures enhanced to show delineated areas of sand and dust and (c) forecast trajectories of air.
 
Sand and Dust Observation Satellite Image Forecast Air Trajectory


         In the above image, areas identified as potential sand or dust are highlighted in yellow to red colours. In general, the thicker and/or denser the sand or dust, the more reddish the colour will be. The base picture is a black-and-white infra-red image showing the temperatures of the observed objects (e.g. clouds). In general, the higher the top of the clouds, the lower its temperature and the brighter it will appear in the image.

Sand or dust weather usually moves by following the background wind, a comparison of images in adjacent times can help bring out their movement and development.

A high concentration of atmospheric water vapour is known to affect the identification of sand or dust. Clouds may mask underlying sand or dust. Deep convections such as thunderstorms may sometimes appear in yellow colours.

        


Last revision date: <21 Dec 2012>