The World Meteorological Organisation (WMO) has reported that sand and dust storms affect 330 million people in more than 150 countries worldwide, causing growing harm to both public health and the global economy.

In the annual WMO Airborne Dust Bulletin, the organisation stressed the need to continue enhancing monitoring, forecasting and early warning systems.

The Bulletin highlighted that although the global average of annual mean dust surface concentrations in 2024 was slightly lower than in 2023, there were big regional variations. In the most affected areas, the surface dust concentration in 2024 was higher than the long-term 1981-2010 average. Every year, around 2,000 million tonnes of sand and dust enter the atmosphere.

More than 80 percent of the global dust budget originates from the North African and Middle Eastern deserts and can be transported for hundreds and even thousands of kilometres across continents and oceans.

Much of this is a natural process, but poor water and land management, drought and environmental degradation are increasingly to blame.

The report, issued to mark the International Day of Combating Sand and Dust Storms on 12th July, noted that while a significant part of the phenomenon is natural, poor water and land management, drought and environmental degradation are increasingly contributing factors.

It added that, in 2024, sand and dust concentrations were lower than the long-term average in many of the main source areas, and higher than average in many areas to where the dust is blown.

The regions that are most vulnerable to long-range transport of dust are: the northern tropical Atlantic Ocean between West Africa and the Caribbean; South America; the Mediterranean Sea; the Arabian Sea; the Bay of Bengal; and central-eastern China. In 2024, the transatlantic transport of African dust invaded parts of the Caribbean Sea region.

“Sand and dust storms do not just mean dirty windows and hazy skies. They harm the health and quality of life of millions of people and cost many millions of dollars through disruption to air and ground transport, on agriculture and on solar energy production,” WMO Secretary-General Celeste Saulo said.

“This Bulletin shows how health risks and economic costs are rising – and how investments in dust early warnings and mitigation and control would reap large returns,” she said. “This is why sand and dust storms are one of the priorities of the Early Warnings for All initiative.”

A new sand and dust storm indicator developed by WMO and the World Health Organisation showed that 3.8 billion people (nearly half the world’s population) were exposed to dust levels exceeding WHO’s safety threshold between 2018–2022. This represents a 31 percent increase from 2.9 billion people (44.5 percent) during 2003-2007.

Exposure varied widely, from only a few days in relatively unaffected areas to more than 87 percent of days, equivalent to over 1,600 days in five years, in the most dust-prone regions. This indicator and the associated findings were published in the Lancet Countdown on Health and Climate Change: 2024 Global Report.

The economic impact is often underestimated, according to a case study from the United States of America. In the USA alone, dust and wind erosion cost an estimated US$154 billion in 2017- more than a fourfold increase over the 1995 calculation.

The estimate included costs to households, crops, wind and solar energy, mortality from fine dust exposure, health costs due to Valley fever, and transport. The true cost of dust was certainly much higher, since reliable national-scale evaluations of many of dust’s other economic impacts (for example, on human morbidity, the hydrological cycle, aviation and rangeland agriculture) were not available, according to the study, which was published in Nature.