Human activities contribute 25 per cent of global dust emissions, with agriculture being the main anthropogenic source, according to the United Nations Convention to Combat Desertification (UNCCD).
UNCCD, which is one of three Conventions that originated at the 1992 Earth Summit in Rio de Janeiro, released policy recommendations during a five-day meeting from November 13-17 in Uzbekistan.
Every year, more than two billion tonnes of sand and dust travel over thousands of kilometres through the Earth’s atmosphere.
Sand and dust storms are a meteorological phenomenon characterised by strong and turbulent winds lifting an ensemble of small particles to great heights. They are known to have adverse impacts on human health, the environment and economies.
Sand and dust storms present a formidable challenge to achieving 11 of the 17 Sustainable Development Goals, according to the United Nations Food and Agriculture Organization (FAO) report Sand and dust storms: A Guide to Mitigation, Adaptation, Policy, and Risk Management Measures in Agriculture.
“It is a costly phenomenon that wreaks havoc everywhere from Northern and Central Asia to sub-Saharan Africa,” Ibrahim Thiaw, UNCCD's Executive Secretary, said in a statement.
The main sources of sand and dust storms are the world’s drylands. About 75 per cent of emissions come from natural sources such as hyper-arid regions, topographic depressions in arid areas and dry ancient lake beds with little vegetative cover.
Global sorces of sand and dust storms
Anthropogenic factors such as land-use change, agriculture, water diversion and deforestation contribute to the remaining 25 per cent.
Abandoned cropland, for instance, are a source of sand and dust storms. Further, water consumption in agriculture shrinks water bodies, creating new sources of sand and dust storms.
For example, the excessive diversion of water from rivers in Central Asia over several decades towards agriculture has shrunk the Aral Sea, a pre-existing lake between Kazakhstan to its north and Uzbekistan to its south. It has now become the Aralkum Desert, a significant new source of sand and dust storms.
Climate change, too, plays a role. Extreme wind events, aridity and frequent, severe and longer droughts worsen the storms.
Other factors such as high air temperature, minimal precipitation and strong winds also act as drivers, the FAO stated.
Sand and dust storms lower the yields and productivity of crops, trees, pastures, and livestock. However, many of these impacts have not yet been well-quantified, according to the FAO report.
For instance, a sand and dust storm that lasted for two days in mid-March 2021 affected an estimated 8,000 people in 2,000 households across 14 of Mongolia’s 21 provinces. Further, 10 people lost their lives and 1.6 million livestock were reported missing.
Also, there is no policy to address the risks posed by sand and dust storms, the FAO report highlighted.
The FAO calls for the establishment of risk monitoring and early warning systems. This, they said, will enable the timely issuing of alerts and early warnings.
The UN body also recommended the strengthening of risk governance of sand and dust storms and increased investment and financing in sand and dust storm risk reduction and impact mitigation measures in agriculture along with developing national capacity and raising awareness of sand and dust storms.