Dust storm or Sandstorm

Primary reference(s)

WMO, 2017. Dust Storm or Sandstorm. International Cloud Atlas, World Meteorological Organization (WMO). Accessed 19 November 2019.

Additional scientific description

Dust storms or sandstorms generally occur in areas where the ground is covered with loose dust or sand. Sometimes, after having travelled great distances, they may be observed over areas where no dust or sand covers the ground. The forward portion of a dust storm or sandstorm may have the appearance of a wide and high wall that advances fairly rapidly. Walls of dust or sand often accompany a cumulonimbus that may be hidden by the dust or sand particles. They may also occur without any clouds along the forward edge of an advancing cold air mass (WMO, 2017).

Metrics and numeric limits

Emissions of sand and dust particles in the air typically have a wind threshold value ranging from about 4 m/s in desert areas to close to 10 m/s in semi-arid regions. As a first approximation, and being fully aware that visibility in sandstorms and dust storms may be influenced by the optical characteristics of the aerosols (chemical composition, particle size spectra) and lighting conditions (solar azimuth, background luminance, presence of medium or high cloud), the following thresholds, which are familiar to human observers and automated systems alike, are recommended (ICAO, 2009):

Examples of drivers, outcomes and risk management

Sand and dust storms are a meteorological hazard, which is related to the process of wind erosion of surface soil and the mineral dust aerosol emission to the atmosphere. They are frequent in northern Africa, the Middle East and Europe, the Arabian Peninsula, Central Asia, northern India, north-western China, southern Mongolia and adjacent Asian countries. In desert regions of Australia and the USA they can seriously threaten human health, agriculture, aviation, ground transportation, the solar energy industry, air quality, infrastructure and industry, as well as aquatic and terrestrial ecological systems. Dust aerosol can carry irritating spores, bacteria, viruses and persistent organic pollutants. Sand and dust storms also transport nutrients to the oceans and affect marine biomass production, which in turn influences greenhouse gas emissions in the marine environment (WMO, 2019).

The World Meteorological Organization Sand and Dust Storm Warning Advisory and Assessment System (SDS-WAS) enhances the ability of countries to deliver timely, quality sand and dust storm forecasts, observations, information and knowledge to users through an international partnership of research and operational communities. It operates through the Global SDS-WAS Steering Committee and three regional nodes: for (i) Northern Africa, Middle East and Europe, (ii) Asia, and (iii) the Americas (Baklanov, 2018).

In terms of health impacts from dust storms and sandstorms, the UNCCD recognizes that sand and dust storms cause numerous human health problems in different regions around the world, especially in arid and semi-arid regions, and that there is a need to reinforce protective strategies to reduce the negative impacts of sand and dust storms on human health (United Nations, 2019).

Examples of national guidance on the health impacts from dust storms and sandstorms include (i) a fact sheet provided by the Australian Government on the health impacts of dust storms where exposure can produce common symptoms that include Itchy or burning eyes; throat irritation; skin irritation; coughing or sneezing; and/or respiratory or breathing difficulties, including asthma attacks (Australian Capital Territory, 2018) and (ii) a guidance sheet on acute exposure and threats to respiratory health prepared by the American Thoracic Society (2018).